[Rattius]

DavidKok, on 2022-August-28, 12:52, said:

I'll do a bit of a writeup myself, trying to keep it brief.
SNIP

I just noticed the up-/down-vote system and I went to upvote your post above David, but it won't let me do that (says I've already used my quota for the day).

Is there something to know, such as new posters can't vote?

[helene_t]

Rattius, on 2022-August-29, 04:06, said:

I just noticed the up-/down-vote system and I went to upvote your post above David, but it won't let me do that (says I've already used my quota for the day).

Is there something to know, such as new posters can't vote?

Yes you need a certain number of posts (maybe 50 or 100?) before you get voting rights.

[helene_t]

Rattius, on 2022-August-28, 11:17, said:

I believe the auction of concern is 1C, passed out. Playing the 1C as forcing removes that issue (and can solve a few other problems too).

This is a concern (unless you play a Mexican 2♦ or similar so that playing 1♣ in a 2-2 fit implies that the board belongs to the opponents) but actually I think the problem is smaller in a short club system than in other natural systems, because usually someone can bid over a 1♣ opening.

Some DD pairs play 1♣ as forcing so that it can include some very strong 3-suited hands (or maybe any GF hand with primarily clubs), but there are also advantages of allowing responder to pass with say 0-4 points and 4+ clubs. For one thing it takes a bit of the pressure of the 1♦ response. Another thing is that if 1♣ is forcing, opps can afford to pass with certain strong hands. For example they may agree that a balanced 16+ count passes first and decides whether to come in in next round, so that a direct 1NT overcall is something artificial.

[Rattius]

DavidKok, on 2022-August-28, 15:24, said:

On the sequence 1♣*-1♦*; 1♥*- 1♠*; 1NT-P responder is only limited by the final pass. In fact, responder more often than not has real diamonds or the 3=3=3=4 10-11 type hand. The fert hands have breakout bids over 1♥, including pass, and will only choose to bid 1♠ relay if 1NT is judged to be playable opposite 11-13. So realistically the combined assets of the partnership on that auction are 16-24.

Having had time to read your system post more carefully and think about it, the 4 options in the 1♦ response don't seem to offer as much protection as it might appear, because they would all "have done something else" by the time 1♣*-1♦*; 1♥*- 1♠*; 1NT - P happens.

As you say, at that point it's known that he has 0-7 (or 0-6 as some top pairs seemed to be playing on VuGraph) and if the weak NT is 11-13 then our man in the pass-out seat knows they have only 11-20 hcp.

So I'd deploy a defence such as Lionel (by Lionel Wright, former world pairs champion) in the pass-out seat - and possibly over the 1♠ relay as well. Using double to show 11+ with ♠ & another (at least 4-4) allows partner to either compete the part score, or to pass whenever we have the balance (and we have the advantage of the opening lead). There are probably other defences that would achieve the same thing, possibly even more penalty-oriented than Lionel. Knowing that we have at least as much as they do and that we get to strike first means, to my mind, that double is almost automatic here especially against vul opponents.

This look like a system weakness - in a standard strong NT system, when we open with the weak NT hand we get to make at least 1 natural bid (the response) which can make it easier to find an escape route. With DD, there are no natural bids at all in the 1♣*-1♦*; 1♥*- 1♠*; 1NT sequence, so effectively you've simply opened an 11-13 1NT at any vulnerability and responder's hand is known to be very weak. However, at least responder gets a chance to run, which they don't get after an opening 1NT - (X*) - P - (P**) - ?

where
* = 11+ ♠ & another
** = pass to play 1NT doubled with 10+ hcp.

In that scenario opener is in the pass-out seat, suddenly lumbered with the last decision and has no knowledge of his partner's hand - since partner may not have acted because he didn't know if they were about to contest the part score or wield the axe.

DavidKok, on 2022-August-28, 12:52, said:

In Dutch Doubleton 1♣ is 99% forcing, but responder may still pass. It just doesn't happen very often since most weak hands can be shown, so pass specifically shows a hand too weak to survive 1NT opposite 17-19 balanced but not enough clubs for a preemptive or inverted raise - something like ♠xx, ♥xx, ♦xxxx, ♣Jxxxx. Also, unlike Polish or Precision, a Dutch Doubleton 1♣ opening is still limited (by failure to open a strong 2♣), but you may stretch that to a decent 24-count with long clubs if you like.

What I understood from commentary is that there's 2 versions of the system, forcing and "semi-forcing", with the latter being as you described.

It also struck me at the time that in the forcing variant, some big hands don't need to open 2C unless they are confident of handling the development of the auction. Hands that would rebid 3 minor are among the worst - bidding space is at a self-inflicted premium. Also 2♣ openers tend to attract interference from good opps so it can become uncomfortable on any hand type - my least favourite auctions are along the lines of: 2♣ - (2♠) - P - (4♠) - ?

It also gives breathing room to a small number of really awkward strong hands with clubs, something like AQxx K AQ AQJxxxx - I'd open this 1♣ but I'd feel much happier knowing I'll get another go.

Apologies, I seem to have got drawn into the theory - and written rather a lot here for someone who hasn't played the game in years!

[Rattius]

helene_t, on 2022-August-29, 04:30, said:

This is a concern (unless you play a Mexican 2♦ or similar so that playing 1♣ in a 2-2 fit implies that the board belongs to the opponents) but actually I think the problem is smaller in a short club system than in other natural systems, because usually someone can bid over a 1♣ opening.

Some DD pairs play 1♣ as forcing so that it can include some very strong 3-suited hands (or maybe any GF hand with primarily clubs), but there are also advantages of allowing responder to pass with say 0-4 points and 4+ clubs. For one thing it takes a bit of the pressure of the 1♦ response. Another thing is that if 1♣ is forcing, opps can afford to pass with certain strong hands. For example they may agree that a balanced 16+ count passes first and decides whether to come in in next round, so that a direct 1NT overcall is something artificial.

Yes I can see there are advantages to passing with clubs and a weak hand and also advantages to playing it as forcing to push some big hands through that route. I remember the BBO commentator making the point re big hands being able to pass over a forcing 1♣ and come in later, although they have to give up some competitive sequences to do so. What strikes me is that a strong NT hand will often have clubs, so any risk involved in a trap pass is limited.

Re the "2-2 fit" scenario, I actually see it the other way round. Theoretically, the fewer clubs the opening side has (after opening 1♣) the more clubs the opposition has, therefore the less likely it is that they can make a t/o double - because if they both have 3+ clubs they are not shape-suitable for a double, so double would only be an option for the (rare) stronger hand types. They are also less likely to have length in other suits, with spaces being taken up by clubs, so the chance of an overcall is reduced too, but perhaps only a little.

In practice, you don't see too many problems with 1♣ openers being passed out in standard strong NT 5cM systems, but I see opponents being too willing to bend their protective bids out of shape, which I don't think is necessarily wise when opponents are playing a system like that. However, a system weakness is always there no matter how often you "get away with it" and has a way of manifesting itself at a bad time. I noticed years ago that the higher the level you play, the more perceptive the opponents become and as I type I'm recalling a national final which we won by 10 IMPs, partly due to a 13 IMP swing in due to opponents having a problem hand type which we understood and exploited (not a hand type directly related to this discussion though - although it was a consequence of a nebulous opening bid).

But... I'm aware that I'm probably getting too involved in the bidding theory for someone who doesn't play the game and was just looking for a system write-up!

P.S. Thanks for the info re number of posts required to vote

[DavidKok]

Rattius, on 2022-August-29, 07:26, said:

Having had time to read your system post more carefully and think about it, the 4 options in the 1♦ response don't seem to offer as much protection as it might appear, because they would all "have done something else" by the time 1♣*-1♦*; 1♥*- 1♠*; 1NT - P happens.

As you say, at that point it's known that he has 0-7 (or 0-6 as some top pairs seemed to be playing on VuGraph) and if the weak NT is 11-13 then our man in the pass-out seat knows they have only 11-20 hcp.

I'm afraid you missed the mark here. There are four options for the 1♦ response to 1♣. In approximate order of frequency:

• Natural diamonds (denies a major suit unless GF).
  
• 0-7 'any' shape (certain hands pass, others give a preemptive raise or a weak jump shift etc. but other than that, all weak hands).
  
• 4=4 majors ~6-11 (you can also claim 8-11, since 7- is covered in the previous option, but the rebid for 6-7 with 4=4 majors is different).
  
• 3=3=3=4 10+ (or, optionally, some (semi)balanced hands with 5 clubs and strength but no desire to give an inverted raise).

If opener responds 1♥ (natural not balanced, or 11-13 any balanced) responder will bid 1♠ with option 1, the upper range of option 2 and option 4. Option 3 bids 1NT, and the lower range of option 2 chooses between pass/2♣/2♦ or even back to 1♠ in a pinch when nothing else is suitable (for example, ♠JTxxx, ♥xx, ♦xx, ♣QJxx, where you will leave opener in some level of clubs opposite the unbalanced hand or transfer to 2♠ opposite the weak balanced hand). Choosing to pass 1NT on the third round of the bidding now shows hand type 1 (with approximately 6-11 points), 2 (with approximately 5-7 points, all really weak hands would run by now) or 4 (with 10-11 points). In a sense, the auction denies the very weak fert you seem worried about.

I play Lionel against strong NT as well (direct seat only), it is a fun but imperfect system of interference.

Rattius, on 2022-August-29, 07:26, said:

What I understood from commentary is that there's 2 versions of the system, forcing and "semi-forcing", with the latter being as you described.


It also struck me at the time that in the forcing variant, some big hands don't need to open 2C unless they are confident of handling the development of the auction. Hands that would rebid 3 minor are among the worst - bidding space is at a self-inflicted premium. Also 2♣ openers tend to attract interference from good opps so it can become uncomfortable on any hand type - my least favourite auctions are along the lines of: 2♣ - (2♠) - P - (4♠) - ?

It also gives breathing room to a small number of really awkward strong hands with clubs, something like AQxx K AQ AQJxxxx - I'd open this 1♣ but I'd feel much happier knowing I'll get another go.

Apologies, I seem to have got drawn into the theory - and written rather a lot here for someone who hasn't played the game in years!

To the best of my knowledge there is no Dutch Doubleton with a 100% forcing 1♣. Instead, there are simply several weak runouts for responder, so that pass is a very descriptive hand type. You might be thinking of Polish club, or similar systems.
Your example hand is opened 1♣ in Dutch Doubleton - responder 'never' has the correct hand type to pass, so you get to have descriptive followups (in this case, most likely 2♠ strong reverse).

[helene_t]

DavidKok, on 2022-August-29, 11:14, said:

To the best of my knowledge there is no Dutch Doubleton with a 100% forcing 1♣.

I thought it was quite common to play 1♣ as 100% forcing, but probably you have a more representative sample than I have so my impression may be coloured by a single write-up (maybe Jansma-Verhees?) or some opponents who may have said it was "forcing" even if it really wasn't.

[Rattius]

helene_t, on 2022-August-30, 02:05, said:

I thought it was quite common to play 1♣ as 100% forcing, but probably you have a more representative sample than I have so my impression may be coloured by a single write-up (maybe Jansma-Verhees?) or some opponents who may have said it was "forcing" even if it really wasn't.

That's the impression I got as well, from the discussion on BBO which included people like David Burn who has acted as captain for various England teams (a role that largely involves advising on counter-measures to opps methods). Perhaps the top players do that but it's not common at lower levels of the game?

[helene_t]

Rattius, on 2022-August-30, 03:39, said:

That's the impression I got as well, from the discussion on BBO which included people like David Burn who has acted as captain for various England teams (a role that largely involves advising on counter-measures to opps methods). Perhaps the top players do that but it's not common at lower levels of the game?

Maybe, but also if some mediocre club players put "DD" on their system card, it may not actually mean DD but just Dutch Acol (or 2/1) modified to 1♣ with 4432. There are also some who play 1♦ as "negative or diamonds" while still rebiding 1NT with 12-14 points. This obviously isn't DD but some pairs may call it DD. Heck, I used to that some 20 years ago

Another thing is that David obviously has more recent exposure to DD so maybe the fashion has changed. I think that Rosalind Hengeveld (who maintains one of the online DD system books) used to play it as forcing but plays it as semi-forcing now.

[Rattius]

DavidKok, on 2022-August-29, 11:14, said:

I'm afraid you missed the mark here. There are four options for the 1♦ response to 1♣. In approximate order of frequency:

• Natural diamonds (denies a major suit unless GF).
  
• 0-7 'any' shape (certain hands pass, others give a preemptive raise or a weak jump shift etc. but other than that, all weak hands).
  
• 4=4 majors ~6-11 (you can also claim 8-11, since 7- is covered in the previous option, but the rebid for 6-7 with 4=4 majors is different).
  
• 3=3=3=4 10+ (or, optionally, some (semi)balanced hands with 5 clubs and strength but no desire to give an inverted raise).

If opener responds 1♥ (natural not balanced, or 11-13 any balanced) responder will bid 1♠ with option 1, the upper range of option 2 and option 4. Option 3 bids 1NT, and the lower range of option 2 chooses between pass/2♣/2♦ or even back to 1♠ in a pinch when nothing else is suitable (for example, ♠JTxxx, ♥xx, ♦xx, ♣QJxx, where you will leave opener in some level of clubs opposite the unbalanced hand or transfer to 2♠ opposite the weak balanced hand). Choosing to pass 1NT on the third round of the bidding now shows hand type 1 (with approximately 6-11 points), 2 (with approximately 5-7 points, all really weak hands would run by now) or 4 (with 10-11 points). In a sense, the auction denies the very weak fert you seem worried about.

I play Lionel against strong NT as well (direct seat only), it is a fun but imperfect system of interference.

To the best of my knowledge there is no Dutch Doubleton with a 100% forcing 1♣. Instead, there are simply several weak runouts for responder, so that pass is a very descriptive hand type. You might be thinking of Polish club, or similar systems.
Your example hand is opened 1♣ in Dutch Doubleton - responder 'never' has the correct hand type to pass, so you get to have descriptive followups (in this case, most likely 2♠ strong reverse).

Hi David, covering the 3 points in your post in order:

(1) So let's examine the sequences, probably simpler to assume that 1♣ - 1♦ - 1♥ has already happened, then we can look at which hands would bid go on to bid 1♠ then pass 1NT:

(i) Natural diamonds hands - presumably they would only bid 1♠ to see what partner's hand type is, then assume captaincy. They would only pass 1NT with no game interest and 5332 so there's one hand type to consider here, 8-10ish with (probably) precisely 5 diamonds-3-3-2? I'm assuming that hands with longer diamonds would rebid 2♦ (and hands with 5 diamonds might consider doing so as well).

(ii) 0-7 hands. I believe that, for the purposes of this exercise, we can ignore the hands that bid 2 minor etc at this stage of the auction since we're only interested in the hands that would bid 1♠ then pass 1NT. Since those are I believe only weak hands, there's nothing in this category to worry about for the defending side if they wish to double 1NT.

(iii) 4-4 majors, 6-11 hands would bid 1NT now (directly over 1♥) so the auction would have started 1♣ - 1♦ - 1♥ - 1NT*, therefore these hands are not possibilities in the scenario we were discussing (1♣ - 1♦ - 1♥ - 1♠ - 1NT - Pass).

(iv) Minimum inverted minor hands. These hands are (almost) all invitational strength so the auction may start that way but it would not end there, responder would be doing something more, not passing. Ok, if you're playing 11-13 you might be passing with 10-11 - also worth noting that, if memory serves, you said that these are your own additions into the system, not part of the standard system itself?

Conclusions. By my calculation that means the only hand type of concern is 8-10 with 5 diamonds - and even that doesn't always mean they have the balance.
Additionally (in your personal version of the system)... 10-11 inverted raise types (if playing 11-13 NT rebid).

So you're right that there is a hand type whereby the opening side could have the balance, but the question in my mind is: is it of sufficient concern/frequency that the defending side should be deterred from looking to penalise when they hear that auction 1♣* - 1♦* - 1♥ - 1♠* - 1NT - Pass? My personal view is that when I hear this auction I'd be looking to penalise as often as possible, when the alternative is to pass out 1NT undoubled. I'd probably want to run a simulation though, which I no longer have the tools to do.

I should add that being doubled is not necessarily the end of the world - there are good run-out systems available and as I mentioned earlier, in the UK many players are quite practised in using them since the 12-14 opening NT is doubled for penalties relatively often (but still not very often in reality).

But one angle my thinking was coming from on this is that you lose an advantage (possibly the only advantage) of the standard strong NT systems' 1X-1Y-1NT in that this is a way of bidding a weak NT that will not be doubled for penalties (responder can have many hand types and strengths, short of game interest) - and if it is doubled then you've made at least one natural suit bid, so escapes should be easier. It's actually that "hard to double" aspect that makes it attractive, since you can open most 11 point hands without the risks of opening a 1NT. I've often thought that this is an area of defensive bidding that should be looked at - why let them play their 1NT rebid any more safely than if it were a 1NT opening?

(2) Re Lionel - I think you can call every bidding method "imperfect"! That's the nature of the beast. But Lionel is good because it has very high frequency and it results in so many good scores, which is why I played it at matchpoints or point-a-board but used another method at IMP scoring where objectives are different.

(3) Indeed, the point of the example hand AQxx K AQ AQJxxxx (rapidly made-up, there's probably better examples) is that it would be opened 1♣ in any natural system, but playing DD opener would be more comfortable knowing that he gets another bid. I used to see some players opening 2♣ on hands like this and usually regretting it for various reasons (lack of bidding space, ill-defined 2♣ system, intervention).
Basically, like you, I see this as a system advantage!

[DavidKok]

I think I've explained it twice already, I'll try a third time but if it still doesn't stick I'm afraid I have nothing more to contribute.

Of the four hand types that are included in the 1♦ response, type 1 (the natural diamonds hands) - can well be 4 diamonds, or 5 diamonds with 4 clubs, or 6 diamonds but a preference for NT - may choose to rebid 1♠ and pass 1NT if game prospects are low. I also mentioned that we play system on over this 1NT, so there is no way to get to 2♦. If you are dealt a hand like ♠Qx, ♥Kx, ♦AJxxxx, ♣Txx I would prefer 1NT to 3♦ (and probably even 2♦!) if partner has a weak notrump, and 2♣ to 2♦ if partner has 4♥5(+)♣. So you rebid 1♠ to ask partner about their holding. It is also worth pointing out that 1♦ followed by 2♦ is a much weaker hand than the example one, and this will (wrongly) heavily discourage partner even with e.g. 17 HCP and a heart-club two-suiter.
Type 2 can also feel that prospects for 1NT are better than 1♥, for example with 7 points and a flat hand (any shape works really, but let's go with 4=2=3=4). Also by not passing out 1♣ (after all, that's a game-going hand opposite 17-19 balanced right there) you now have a choice between pass and 1♠, but the relay stands to gain a lot when partner is unbalanced, and cost very little when partner has got the balanced minimum. So it is correct to bid on. In fact, this also applies to slightly better shape or one or even two points less.
Type 4 is also not the non-issue you pretend it is. If you read back you'll see that I said that 3=3=3=4 is common, and including other hand types like 2=3=3=5, or maybe 4=3=3=3 strong (both of which I do not include) is theoretically sound but a matter of partnership preference. These hands indeed prefer to take captaincy and keep asking, and when holding 10-11 (or even a nice ~8-9-count that doesn't want to hog the hand) passes out 1NT since there are no game prospects.
Your conclusions are identical to last time, and equally wrong.

[Rattius]

DavidKok, on 2022-August-30, 14:27, said:

I think I've explained it twice already, I'll try a third time but if it still doesn't stick I'm afraid I have nothing more to contribute.

Of the four hand types that are included in the 1♦ response, type 1 (the natural diamonds hands) - can well be 4 diamonds, or 5 diamonds with 4 clubs, or 6 diamonds but a preference for NT - may choose to rebid 1♠ and pass 1NT if game prospects are low. I also mentioned that we play system on over this 1NT, so there is no way to get to 2♦. If you are dealt a hand like ♠Qx, ♥Kx, ♦AJxxxx, ♣Txx I would prefer 1NT to 3♦ (and probably even 2♦!) if partner has a weak notrump, and 2♣ to 2♦ if partner has 4♥5(+)♣. So you rebid 1♠ to ask partner about their holding. It is also worth pointing out that 1♦ followed by 2♦ is a much weaker hand than the example one, and this will (wrongly) heavily discourage partner even with e.g. 17 HCP and a heart-club two-suiter.
Type 2 can also feel that prospects for 1NT are better than 1♥, for example with 7 points and a flat hand (any shape works really, but let's go with 4=2=3=4). Also by not passing out 1♣ (after all, that's a game-going hand opposite 17-19 balanced right there) you now have a choice between pass and 1♠, but the relay stands to gain a lot when partner is unbalanced, and cost very little when partner has got the balanced minimum. So it is correct to bid on. In fact, this also applies to slightly better shape or one or even two points less.
Type 4 is also not the non-issue you pretend it is. If you read back you'll see that I said that 3=3=3=4 is common, and including other hand types like 2=3=3=5, or maybe 4=3=3=3 strong (both of which I do not include) is theoretically sound but a matter of partnership preference. These hands indeed prefer to take captaincy and keep asking, and when holding 10-11 (or even a nice ~8-9-count that doesn't want to hog the hand) passes out 1NT since there are no game prospects.
Your conclusions are identical to last time, and equally wrong.

David, I genuinely thank you for your responses and I really hope that your attempt to help doesn't end on a sour note. I do appreciate it and I hope we can say adieu in good spirits

However I have to say that I still believe that my analysis is correct. I think some of the scenarios under discussion require that we bear in mind at all times two key points:

(1) We are only talking about one specific sequence (1♣ - 1♦ - 1♥ -1♠ - 1NT - Pass) AND
(2) That the sequence in question means responder has less than an invitational hand (or he would not be passing 1NT). The final Pass is important here - it tells us that responder has less than invitational strength.

I really don't mean to be confrontational when I say that I'm not sure that both of those key points have always been borne in mind in your analysis. Looking at your most recent post:

1. The hand you mention with diamonds I have already acknowledged to be the hand type that could lead to the opening side having the balance (some of the time) in the sequence of interest. But, when that hand passes 1NT it is limited by its failure to invite game (assuming competent opponents). Hence the 8-10 range mentioned in my previous post. I guess an 11 count might/would also pass opposite an 11-13 NT rebid.

2. The hand with 7 points that you give as an example brings the opening side's total hcp to a mere 18-20, since the 1NT rebid shows 11-13. Ergo, in that example they clearly do not have the balance of strength. It's not about choosing to relay over 1♥, it's about the fact that doing so and then passing 1NT tells a story.

3. Type 4 may have additional strength and other shapes possible (with clubs of course) but... once again, the hands that would follow the sequence of interest, including responder's final pass over 1NT, are those that are sub-invitational, hence 10-11. A 12 count would make a game try opposite an 11-13 NT so it is not within the scenario of interest (because it would not make the final pass in the sequence).

This is the reason I believe the 1NT should be a target for a penalty double - because the final Pass tells us that they (almost certainly) don't have enough to make it.

I think there was also some confusion at times as to which hand types were being discussed e.g. when you say "no way of getting to 2♦", that was said in a different context than being bid after 1NT. But hey, as you say, let's end it there - you've kindly summarised and then pointed me at a write-up of the system and that helps, so many thanks for that, much appreciated.

P.S. Although I found that write-up before, I couldn't translate it until I read your post - then I became more persistent and tried it directly through the Google translate page on a different browser - it seems it only works on Chrome or MS Edge. Learn something every day

[DavidKok]

I use Firefox and the translate link works just fine, I'm not sure what the difference is.

Rattius, on 2022-August-30, 16:09, said:

This is the reason I believe the 1NT should be a target for a penalty double - because the final Pass tells us that they (almost certainly) don't have enough to make it.

This is the part where the story goes off the rails. You correctly identify a list of hands where this auction shows 21-24 combined HCP, and then a few more situations where it shows 17-20. It is extremely risky to double for penalties - 1NT has decent odds of making at only 19HCP combined, I suspect opener+responder will have 20+ HCP more often than not (which is why your 'almost certainly' is so frustrating - you keep repeating it, without acknowledging that the underlying distribution of combined HCP is completely different from what you are suggesting). Lastly responder is in a great position to run when it is right, and sit when it is not. As I've pointed out in the second rebuttal most of the 0-7 range hands are excluded from the given sequence, so the chance of catching a fat 1100 or so are nonexistent (unlike when one opens a weak notrump, responder passes and the fourth hand it strong - on the Dutch Doubleton sequence most very weak responder hands would have settled for one of 1♣, 1♥, 2♣ or 2♦ instead). I think this is actually a terrible auction for penalty doubles, if you wanted to enter the auction you should have done so two rounds ago. The sequence does not show weakness, rather it usually claims the balanced of the points but sometimes might have as little as 16HCP or so combined. But I think the tail on that distribution is narrow enough that you're chasing a ghost with the belated penalty double.

[Rattius]

DavidKok, on 2022-August-30, 17:41, said:

I use Firefox and the translate link works just fine, I'm not sure what the difference is.

This is the part where the story goes off the rails. You correctly identify a list of hands where this auction shows 21-24 combined HCP, and then a few more situations where it shows 17-20. It is extremely risky to double for penalties - 1NT has decent odds of making at only 19HCP combined, I suspect opener+responder will have 20+ HCP more often than not (which is why your 'almost certainly' is so frustrating - you keep repeating it, without acknowledging that the underlying distribution of combined HCP is completely different from what you are suggesting). Lastly responder is in a great position to run when it is right, and sit when it is not. As I've pointed out in the second rebuttal most of the 0-7 range hands are excluded from the given sequence, so the chance of catching a fat 1100 or so are nonexistent (unlike when one opens a weak notrump, responder passes and the fourth hand it strong - on the Dutch Doubleton sequence most very weak responder hands would have settled for one of 1♣, 1♥, 2♣ or 2♦ instead). I think this is actually a terrible auction for penalty doubles, if you wanted to enter the auction you should have done so two rounds ago. The sequence does not show weakness, rather it usually claims the balanced of the points but sometimes might have as little as 16HCP or so combined. But I think the tail on that distribution is narrow enough that you're chasing a ghost with the belated penalty double.

List of hands? I identified one very specific hand - 8-10/11 with diamonds. There's also one other equally specific hand in your personal version of the system (10-11 with clubs). I don't think it's really valid to call that "a list" of hands where the opening side has the balance.

That's why I cannot understand why you "suspect" that the opening side "will have 20+ HCP more often than not" - I believe that I laid out exactly why that is clearly not the case. It's quite clear to me that on the vast preponderance of hands the "other side" will have the balance. And the other situations are in the range 11-20 not 17-20 (11 opposite zero is the worst case here).

I would also dispute that "1NT has decent odds of making at only 19 HCP combined" - I've defended 1NT doubled more than enough times to know that it almost always goes off when the defending hands have the lead and the balance of strength, roughly equally divided. Note also that I wasn't suggesting that you simply double all of those auctions without further thought - I suggested a defence such as Lionel which looks to either penalise when we have the balance or to compete the part score otherwise. As I noted when I first mentioned it, there are probably (even) better ways to defend this scenario. The possibility of a run-out doesn't stop us doubling, we then hunt their run-outs (I found a forcing pass/take-out double approach best over their first bid).

Getting into an auction once the opposition have told you that you almost certainly have the balance is simply good bridge - not doing so is the opposite. Having methods that allow you to tell that it's one of the rare occasions when you don't have the balance can only help avoid a bad time to double (whereupon you compete the partscore instead).

And you don't do it for 1100s, although they will happen occasionally, the lesser scores are also very worthwhile - at the risk of letting them make 1NT doubled now and again. No big deal.

I think we've put enough into this now - especially for me as someone who doesn't even play the game any more! So I'll thank you again for your help and wish you goodbye David. All the best.

[michel444]

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