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How semi is semiforcing Why not just play 2/1 with a "non-forcing" 1NT?

#1 User is offline   mgoetze 

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Posted 2010-December-16, 17:12

Let's say I start off playing standard 2/1, whatever that is. Then someone shows me some neat gadget for handling a 3-card limit raise of 1M, say by stuffing it into 2. Then someone tells me I can switch to a "semi-forcing" 1NT if I play jump shifts as natural and invitational. I ask what this semi-forcing 1NT is and it is explained to me that it is like a forcing 1NT except that I can pass if I have a balanced minimum. I take this to mean 5332 shape with less than an opening 1NT.

The story could end here. But let's talk about it some more. Say I hold

and decide to open 1. Partner bids 1NT, "semiforcing". I don't have a balanced hand, so I'm supposed to bid something. 2 is obviously out of the question. Some people, it's rumoured, would rebid 2. They probably aren't playing Gazzilli. I even suspect they're not playing matchpoints. That leaves 2. Will I be able to say "Thank you, partner," if he tables a 3154 hand?

So I pass. An extreme example, you say. It wasn't systemic, it was a "tactical bid", I was applying "judgement". I guess they're saying I shouldn't do it again when I hold a small diamond and the Ace of spades?

Playing the aforementioned Gazzilli convention, what if I hold

Sure, my clubs are decent. I could call this "clubs or strong". But really... why should I? 1NT is a great contract. Everyone loves 1NT. Especially at matchpoints!

My question is, which hands does the so-called "semiforcing 1NT" still contain which are not in a standard non-forcing 1NT. Obviously there are some invitational hands in there which don't have a good enough suit for a jump shift. But if they plan to invite me, they will do so in vain, for I will not be accepting with the aforementioned hands.
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#2 User is offline   gwnn 

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Posted 2010-December-16, 17:42

huh? if you're playing semiforcing NT, you can and should pass with a 4513 12 count
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#3 User is offline   blackshoe 

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Posted 2010-December-16, 17:48

View Postmgoetze, on 2010-December-16, 17:12, said:

My question is, which hands does the so-called "semiforcing 1NT" still contain which are not in a standard non-forcing 1NT.


All the hands which are in a "forcing 1NT" and not in a standard non-forcing 1NT except the three card limit raise. At least, that's how I learned it.
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#4 User is offline   Fluffy 

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Posted 2010-December-16, 18:13

You should be careful not to pass hands that accept game if partner rebids 2NT, otehr than that, feel free to pass with whatever
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#5 User is offline   awm 

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Posted 2010-December-16, 18:16

Semi-forcing is a rather stupid name.

The idea is that the 1NT response still contains hands up to a bad 12 hcp. So you can't pass when you've opened something that wants to be in game opposite a bad 12 hcp.

Thus there are some hands which would pass a standard american "non-forcing" notrump with a range up to a bad 10 hcp, but which must take another call opposite the "semi-forcing" notrump. These are hands like a (5332) hand with 14-15 hcp, or a 45xx hand in roughly the same point range. These hands rebid the longer minor suit, much as they would if 1NT was forcing.
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#6 User is offline   mgoetze 

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Posted 2010-December-17, 03:52

View Postgwnn, on 2010-December-16, 17:42, said:

huh? if you're playing semiforcing NT, you can and should pass with a 4513 12 count


Well yes, I agree. But that's not really the way it's taught, and I've not found a good explanation, so I want to work it out. Should I also be passing with 3541 12 counts? And so on.
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#7 User is offline   the hog 

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Posted 2010-December-17, 04:45

[quote name='mgoetze' timestamp='1292579527' post='516003']
Well yes, I agree. But that's not really the way it's taught,
According to whom? Please supply links.
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#8 User is offline   mgoetze 

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Posted 2010-December-17, 06:12

View Postthe hog, on 2010-December-17, 04:45, said:

According to whom? Please supply links.


Wikipedia: "...except that the opener is allowed to pass with a 5-3-3-2 minimum..."

Karen McCallum: "[O]pener can pass with a balanced 12 or 13 pts."

Larry Cohen: "Note: If you prefer, treat 1NT as 'semi-forcing.' This still means 6-12, but opener is allowed to pass if he has a flat minimum (5-3-3-2)."

Many others...
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#9 User is offline   mgoetze 

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Posted 2010-December-17, 06:25

(wrong thread lol)
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#10 User is offline   gwnn 

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Posted 2010-December-17, 06:25

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#11 User is offline   Free 

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Posted 2010-December-17, 06:39

Semi forcing basically means that you are allowed to pass whenever you'd pass a balanced invite. I'm pretty sure you won't bid game if partner rebids 2NT on any of the 2 hands, so both hands are passable. But with 14HCP and 5M332 you'd bid 3NT so you can't pass these hands.

This doesn't mean you have to pass ofcourse. The first hand could easily make 5 opposite some length and shortage. If you really want to bid something, bid 2 (after a forcing 1NT this shows (2)3+, it's exactly the same after semi forcing 1NT).

No idea why you mention Gazzilli here, it's completely irrelevant and is sometimes even worse on such hands.
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#12 User is offline   mgoetze 

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Posted 2010-December-17, 06:55

View PostFree, on 2010-December-17, 06:39, said:

No idea why you mention Gazzilli here, it's completely irrelevant and is sometimes even worse on such hands.


I think it's because I don't understand the rebid-2m-on-three-cards philosophy.
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#13 User is offline   gnasher 

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Posted 2010-December-17, 07:03

I think that there are three categories of notrump response:
(1) Opener always bids.
(2) Opener bids with some balanced hands that are too weak to open 1NT.
(3) Opener passes with all balanced hands that are too weak to open 1NT.

There is often not much logic in bridge terminology, but it seems sensible to me that if we're going to use the term "Semi-forcing" to mean anything, it should mean (2).

By the way, even playing a "non-forcing" notrump, I'd rebid 2 with J98x KJ8xx A QJx or J10 KQxxx 9x AQ10x.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
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#14 User is offline   mgoetze 

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Posted 2010-December-17, 07:16

View Postgnasher, on 2010-December-17, 07:03, said:

By the way, even playing a "non-forcing" notrump, I'd rebid 2 with J98x KJ8xx A QJx


I'd appreciate it if someone could explain the advantages of this style to me.
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Posted 2010-December-17, 07:17

View Postgwnn, on 2010-December-17, 06:25, said:

Name is a fence and within it you are nameless. ~Samuli Paronen


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#16 User is offline   Ant590 

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Posted 2010-December-17, 09:08

View Postmgoetze, on 2010-December-17, 06:55, said:

I think it's because I don't understand the rebid-2m-on-three-cards philosophy.


It's because people have decided they'd like to show 6 cards in the major with a 2M rebid. So, you have to park some of the 5M hands elsewhere.

If you're happy rebidding the major with 5 then you don't need a 2m-on-three-cards rebid
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#17 User is offline   jschafer 

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Posted 2010-December-17, 09:37

As I understand it, a forcing 1NT contains hands that can be subdivided into:

- Very weak raise of 1M, unsuitable for a preempt or direct raise.
- Invitational 9-11 hands with a 6+ suit (unless you play 1M-3X as showing this).
- Balanced invitational hands 10-11(12) hcps without fit (no 4 over 1).
- Invitational raises with fit (but no 4 over 1).
- (5)6-9 hands without fit or 4 over 1 (can have long side suit). Pretty much the same hands as a non-forcing 1NT bid.

Bearing that in mind you most should be bidding on most (12)13-14 hcp balanced hands regardless of shape because:

a) Game still has good chances opposite several of responder's possible hands.
eg. Hand 1 partner could have a nice invitational hand with a strong 6+ or suit, making 3NT decent.

b ) Still a fair few hands that can have support for major, which may play better than 1NT (and make game).
eg. Limit raise opposite your Hand 1 has good chances of making 4

c) Partner can still have weak hand with a long side suit that may play much better than 1NT.
eg. Hand 2 partner could have a really good hand with long s which rates to be better than 1NT, the opponents can probably make/sac 2 anyway and have better chances of bidding it if you pass 1NT.

d) You could be preempting the opps from getting in if it is their hand.
eg. Hand 1 partner could have a really weak raise in s and you are preempting them out of their fit.

e) Partner can have a fit for your minor suit on 5422 hands, so it pays off when you bid them.
eg. on Hand 2 if partner doesn't have major support he will not have 4, you could easily be better off in or .

f) Even if partner doesn't have one of the nice hands above, it doesn't mean you will get a bad score. At IMPs there usually isn't a big difference between a suit partscore or 1NT on most hands anyway. A lot of the time you will just end up in a 5-2M fit in 2M when partner doesn't have a great hand for you and they really aren't such a bad thing anyway (even at MPs). Sometimes the opps still decide to get into the auction at their own peril. You are eating up a lot of bidding space with still relatively undefined hands, making life pretty tough on the opponents.

Anyway, that is why I would bid on on most hands as opposed to Pass. In the worst case scenario you might end up in a 5-2 Major fit or the occasional dodgy contract but imho there are many ways to gain by bidding whenever you are unbalanced. Obviously if you open some 11hcp balanced hands NV or a really nasty 4333 12-count then is safer to Pass over 1NT.


EDIT: bidding 3c minor suits is better than rebidding 5M suits because it lets you play there when partner hates your major but has a weak hand with that suit (or if you rebid s). Partner will usually correct to 2M anyway when he has 2card support and no other good strain to play in. It leaves more room to get to the best contract.

This post has been edited by jschafer: 2010-December-17, 09:43

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#18 User is offline   mgoetze 

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Posted 2010-December-17, 11:08

Thanks Jorrit, this is the kind of answer I was hoping for. So basically, if I move...

View Postjschafer, on 2010-December-17, 09:37, said:

- Very weak raise of 1M, unsuitable for a preempt or direct raise.


...these hands to pass or 2M...

Quote

- Invitational 9-11 hands with a 6+ suit (unless you play 1M-3X as showing this).


...these hands to 3x...

Quote

- Invitational raises with fit (but no 4 over 1).


...and these hands to 2, I am left with only...

Quote

- Balanced invitational hands 10-11(12) hcps without fit (no 4 over 1).
- (5)6-9 hands without fit or 4 over 1 (can have long side suit). Pretty much the same hands as a non-forcing 1NT bid.


...these hands to worry about. Which means I can pass with any hand up to a bad 13.

Do things change, though, if for instance I add suit quality requirements to the invitational jumps? Will I miss a game when partner bids 1NT on AKx x KJx xxxxxx? That is the sort of thing I'm interested in.
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#19 User is offline   awm 

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Posted 2010-December-17, 13:30

Well you've removed all the game-invitational hands except for ones that would normally rebid 2NT if you played a forcing notrump. And the hand that passes 1NT is that hand that would pass 1M-1NT-2x-2NT. Under that reasoning, you're not really missing any games that you wouldn't have missed anyway.

It's true that occasionally responder would raise opener's second suit, so you might see 1M-1NT-2x-3x if you played forcing notrump, and instead you get 1M-1NT-Pass. However, the 3x raise has a pretty wide range (actually wider than a 2NT invite), so it's unlikely that there are many hands which are sufficiently "upgraded" to accept the 3x invite (keep in mind that it's a minor suit, that opener rebid it on three cards so there's no huge fit known to opener, and that 3x has a somewhat wide range).

By playing semi-forcing notrump in this manner, you don't miss any games that you would've bid otherwise. You get to play 1NT on some hands where you would've played 2NT otherwise, which is always good. You play in 1NT instead of 2M on some hands, which can be a win (double dummy it seems like a wash, but 1NT is a tough contract to defend). You do occasionally miss a better partial in responder's long suit (i.e. say responder has 6 and a weak hand after 1-1NT-Pass). However, this method also makes it more comfortable for responder to raise opener's minor-suit rebid on four-card support, knowing that opener will normally have either a four-card suit (so you have a real fit) or sufficient extras to accept an invite.
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#20 User is offline   jschafer 

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Posted 2010-December-17, 14:03

I haven't played the 1M-3x with suit quality requirements before, so the short answer to your question is that I'm guessing as much as you are here :)

However, I think part of your question depends on your what your quality requirements are. If you just want to sort out the ones with no honours whatsoever in the 6+ suit invitational hands then I doubt it will make a difference to your rebids over 1NT because they will account for a very small fraction of all 1NT responses. The 1M-3x bids are rare as it is and when they do come up you will almost always have an honour in them. I did a quick check on the BBO deal source generator thing and the first 30 hands it came up with all had suits headed by the Q or better. The low frequency of the hands means you won't be losing much by putting them in 1NT and not rebidding differently, but it also means you won't be gaining much frequency-wise because they wouldn't have been in most of the original 1M-3x bids anyway. If you send these hands via 1NT to 3 it also means you have to give up on extremely weak hands with really long minor suits (eg. over 1-1NT-2-?), which you can no longer bid nicely (they are rare too though).

I would suspect that in order to make your invitational long suit bids worth splitting up, you want to divide them into quality criteria that actually make them worth splitting in terms of hand evaluation for partner for bidding 3NT and with regards to frequency (eg. 5+ hcps in suit vs less than 5 in suit). The more strong hands you put into 1NT though, the lighter you may have to end up rebidding over 1NT because you might be worried about missing game if your side suit is AKx in a minor. I have no idea whether your suit quality criteria would be a gain or not over the standard treatment, but it seems like it would be nice to try out :D
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