[nullve]

Consider the (wildly hypothetical) auction

W N E S
(...)
c P P P,

where the call c and the first two passes are "forcing".

Apparently someone's got the idea of forcing wrong. But who? And why?

[helene_t]

E's pass can't be forcing obviously.

East and South both passed a forcing call. Maybe E can be excused because the forcing pass by North suggested that NS have the balance of power? And/or maybe South can be excused because the nonsensical explanation of East's pass suggest that EW are messing it up? This will all depend on the meaning of the first three calls, beyond just "forcing".

[nullve]

We all know what the fundamental purpose of a force is: to make sure that the player making the forcing call will get the chance to make another call. This will happen automatically if LHO makes a call other than pass, and a proper definition of 'forcing call' should reflect that, unlike the following definition of 'forcing bid':

"A bid that, by partnership understanding, requires the bidder's partner to make another bid." (https://en.wikipedia...ct_bridge_terms).

And unlike

"In the card game contract bridge, a forcing bid is any call that obliges the partner to bid over an intermediate opposing pass." (https://en.wikipedia...iki/Forcing_bid),

a proper definition might also take into account the nature of LHO's pass, since e.g. in the extreme case that P by LHO forces RHO to bid no matter what (as on a literal interpretation of the first definition of 'forcing bid' above) it might seem that partner (of the player making the initial forcing call) should again be exempted from bidding.

[helene_t]

That north's pass is forcing is nonsense since he will always get another turn.

[nullve]

helene_t, on 2016-August-03, 05:11, said:

That north's pass is forcing is nonsense since he will always get another turn.

Not sure why you say it's nonsense. If 'forcing call' is defined along the lines of 'forcing bid' above, e.g. as a call that doesn't allow partner to pass, then whether West's call is forcing is completely irrelevant.

But if West's call is forcing in the sense that East can be trusted to bid regardless of the meaning of North's pass, then I grant it will be superfluous (as well as highly unusual) to describe even an unlimited wait-and-see pass by North as forcing, as he will always be able to make another call. But suppose the bidding goes

W_N_E_S
2♦ P,

where 2♦ is standard Multi and North's pass is not only wait-and-see but (for some stupid reason so I can make my point) promising 20+ hcp. Do we really think that a systemic pass by East in this situation is inconsistent with 2♦ being forcing in the sense we want to use the word? If not, might it not be appropriate to describe North's pass as forcing, too, as South might not be allowed to pass if East does?

A less contrived example, perhaps:

W_N_E_S
P¹ P² P<sup>3

1</sup> 13+, any ("strong pass")
² 13+, any ("strong pass vs. strong pass")
³ systemic gamble, knowing that pass by South will be a comparable gamble

Is West's pass forcing? If so, what about North's?

[nullve]

nullve, on 2016-August-04, 04:45, said:

where 2♦ is standard Multi and North's pass is not only wait-and-see but (for some stupid reason so I can make my point) promising 20+ hcp.

Less ridiculous: suppose NS play, or are just testing, a new defence against Multi where

P = opening strength, unlimited, catchall. Advancer is not allowed to pass if Responder does.
X = less than opening strength
2♥+ = standard.

[nullve]

Continuing my monologue: I'm starting to think that our usual notions of forcing really belong in a 2-handed bidding context, where e.g. the sequence

1♦-1♥

is supposed to mean the same thing as

1♦-(P)-1♥-(P)

in the 4-handed context, except that the intervening passes are treated as emtpy words (that can be omitted) rather than calls on par with 1♦ and 1♥.

[nullve]

How about

Def.: A call is

* 'never forcing' if partner is allowed to pass over an intervening pass of any kind;
* 'always forcing' if partner is not allowed to pass over an intervening pass of any kind;
* 'sometimes forcing' if it is neither never forcing nor always forcing.

?

Or maybe a call should be sometimes forcing if it's not never forcing (so that always forcing implies sometimes forcing, but not vice versa)?

[Zelandakh]

Sorry but this whole thread is complete ********. Forcing means partner gets the opportunity to speak again. It does not matter if that is through our bidding or the opps bidding. If you or the opps are describing calls as forcing and then passing in a situation where partner is not likely to get another chance to bid then there is MI being given. There is not a lot else to say beyond what Helene already contributed.

[nullve]

Zelandakh, on 2016-August-08, 05:58, said:

Forcing means partner gets the opportunity to speak again. It does not matter if that is through our bidding or the opps bidding.

I don't disagree.

Zelandakh, on 2016-August-08, 05:58, said:

If you or the opps are describing calls as forcing and then passing in a situation where partner is not likely to get another chance to bid then there is MI being given.

Does

2♦¹-(P²)-P

¹ Weak 2M or 20-21 bal., F1
² 13+

qualify?

The point is that when we describe certain calls as "forcing", whether at the table, on the CC or in our detailed system notes, we typically don't consider all outlandish meanings that a pass by LHO could have.

[Zelandakh]

nullve, on 2016-August-08, 06:46, said:

I don't disagree.

Does

2♦¹-(P²)-P

¹ Weak 2M or 20-21 bal., F1
² 13+

qualify?

It qualifies in as much as the forcing nature of 2♦ is questionable. If I have a very weak hand with long diamonds it is logical to pass. Similarly, if second hand's pass is described as forcing and 4th hand is passing because "Opener has a guess" or whatever it was you wrote before for this then they are not disclosing properly, as the guess has not changed since the agreement was made. I understand what you are saying and stand by my evaluation of the thread.

[rbforster]

One's agreements on forcing bids varies in uncontested and competitive auctions. You can play 2/1 system with a forcing NT where opener is 100% expected to bid again after

1M-(p)-1NT(f)-(p)
?

But very few people would play opener was forced to bid if the auction went

1M-(p)-1NT(f)-(2♣)
?

Obviously your bid depends on the competitive action taken by the intervening bidder over the forcing-if-uncontested bid by partner. When intervenor passes showing weakness, you use your "uncontested" methods. When intervenor bids, you use your competitive methods including giving opener the option of passing, doubling, etc, with potentially different meanings than they would have had in the uncontested auction.

In this context, it's not unreasonable for a bid over an intervening strong or unusual pass by opponents to mean something different, and potentially including pass as an option. The part where it gets tricky is in competitive auctions with an unusual pass by opponents, unlike a competitive bid by the intervening opponent, the competitive pass doesn't give partner a guaranteed second call and this can be very troublesome since he made a forcing bid that will often not be a contract he wants to play in. So when dealing with designing competitive methods over competitive passes, there are a lot more subtleties and more game theory (if I pass his forcing pass, how likely is his partner to be forced to bid) that go into assigning good defensive meanings to your bids over their unusual pass.

[nullve]

Zelandakh, on 2016-August-08, 08:01, said:

If I have a very weak hand with long diamonds it is logical to pass.

Yes. I should have included a GF option in Multi, although pass might still be a reasonable gamble on some hands.

Zelandakh, on 2016-August-08, 08:01, said:

Similarly, if second hand's pass is described as forcing and 4th hand is passing because "Opener has a guess" or whatever it was you wrote before for this then they are not disclosing properly, as the guess has not changed since the agreement was made.

I think you're referring to the auction where the two first calls (passes) were just described as "13+, any ("strong pass")" and "13+, any ("strong pass vs. strong pass")", respectively. (I.e. no mention of forcing.) But if your point is that NS cannot both describe North's call as forcing and yet have the agreement that South is sometimes allowed to end the auction with a pass (as in the OP auction), then I agree.

But I'm also trying to make the point that if a pair started thinking about the possible meanings that an intervening pass could have, they might revise or abandon some of their old ideas about forcing. Of course,

"Forcing means [the player making the call] gets the opportunity to speak again."

still applies, but the implementation might be different.

This post has been edited by nullve: 2016-August-09, 04:47

[nullve]

rbforster, on 2016-August-08, 08:18, said:

The part where it gets tricky is in competitive auctions with an unusual pass by opponents, unlike a competitive bid by the intervening opponent, the competitive pass doesn't give partner a guaranteed second call and this can be very troublesome since he made a forcing bid that will often not be a contract he wants to play in. So when dealing with designing competitive methods over competitive passes, there are a lot more subtleties and more game theory (if I pass his forcing pass, how likely is his partner to be forced to bid) that go into assigning good defensive meanings to your bids over their unusual pass.

Yes. And this is one reason why we might do better than describing our calls as "forcing", which would amount to MI if we made use of pass over their unusual but non-forcing pass.

This post has been edited by nullve: 2016-August-09, 12:27

[nullve]

Part of Chip Martel's defence to Swedish Club (described here):

(1♣)-?:

P = weak, unsuitable for 1♥+¹ / opening strength, unsuitable for a standard 1♦ or 1M opening
X = standard 1M opening
1♦ = standard 1♦ opening
1♥+ = destructive

I wonder what Advancer is supposed do over

(1♣)-P-(P).

Of course, that might depend on the meaning of Responder's pass.

¹ Not mentioned by Martel, but I don't think he's prepared to overcall 1♥+ on all weak hands.

This post has been edited by nullve: 2016-August-20, 16:15

[Stefan_O]

nullve, on 2016-August-02, 05:11, said:

Consider the (wildly hypothetical) auction

W N E S
(...)
c P P P,

where the call c and the first two passes are "forcing".

Apparently someone's got the idea of forcing wrong. But who? And why?

I am not sure what the motivation behind this question was, but...

To me it's totally clear that East is the first player who takes a gamble and risks messing things up.
If you wish to retain your pd's confidence, you can never trust your opponents to uphold neither their own agreements, nor yours.

Afaik (and hopefully), there is still no law against passing a forcing bid.
If pd opens a strong 2C, and you decide to gamble on a Pass, you are free to do so.
You're pd might of course decide never to play with you again, but it's your decision totally.
(btw, how can East's Pass in response to his pd's forcing bid, ever be defined as "forcing"? That sure is nonsense.)

Anyways, after Easts Pass, the next player to test his luck, putting his head in the guillotine to see what good might come out, is South...

If West's bid was, for example, some Polish forcing 1C opening, and NS's agreement was that North's Pass is forcing,
and then South, holding 3334+0 hcp, decides to gamble on a Pass,
he will no doubt painfully and fairly learn -- according to Murphy's law -- that the Polish opener, in accordance with their CC, held a balanced 10 hcp,
North held the remaining 30 hcp in a monster hand and South's 3-card spade support was exactly what he needed to make the grand in his own hand.

Ehrrr... sorry... what was the question, again...?

[nullve]

Stefan_O, on 2016-September-06, 12:16, said:

I am not sure what the motivation behind this question was, but...

To me it's totally clear that East is the first player who takes a gamble and risks messing things up.

[...]

Afaik (and hopefully), there is still no law against passing a forcing bid.

I agree. But East might argue that it's highly improbable that South will pass unless MI was given when North's pass was described as forcing.

Stefan_O, on 2016-September-06, 12:16, said:

If you wish to retain your pd's confidence, you can never trust your opponents to uphold neither their own agreements, nor yours.

I can think of exceptions. For example, in order to apply LoTT successfully one will often have to assume that opps have approximately the number of trumps they say they have.

Stefan_O, on 2016-September-06, 12:16, said:

(btw, how can East's Pass in response to his pd's forcing bid, ever be defined as "forcing"? That sure is nonsense.)

If a forcing call "any call that obliges the partner to bid over an intermediate opposing pass", then I completely agree with you: East's pass can't be forcing unless West is allowed to violate a basic law of bidding. And even if a forcing call is lazily defined just a call that requires the bidder's partner to make another bid, it can only make sense to describe East's pass as forcing if South can somehow be trusted to bid over North's "forcing" pass. Well, can he? Not absolutely, of course, since South doesn't violate any law by passing unless he does that often, in which case MI was given by describing North's pass as "forcing". So it might not make much difference to East in practice whether South always bids or if he chooses to pass once in a blue moon. But then it might not seem very inaccurate to describe East's pass as forcing in the latter sense either. (Whether it can in any way be useful to describe East's pass as forcing is another matter...)

But bottom line: I agree with you.

Stefan_O, on 2016-September-06, 12:16, said:

Anyways, after Easts Pass, the next player to test his luck, putting his head in the guillotine to see what good might come out, is South...

If West's bid was, for example, some Polish forcing 1C opening, and NS's agreement was that North's Pass is forcing,
and then South, holding 3334+0 hcp, decides to gamble on a Pass,
he will no doubt painfully and fairly learn -- according to Murphy's law -- that the Polish opener, in accordance with their CC, held a balanced 10 hcp,
North held the remaining 30 hcp in a monster hand and South's 3-card spade support was exactly what he needed to make the grand in his own hand.

Murphy's Law will also tell you to never make an opening preempt, because LHO will always have the remaining cards in your long suit, and they will always double you.

[Stefan_O]

nullve, on 2016-September-07, 03:38, said:

Murphy's Law will also tell you to never make an opening preempt, because LHO will always have the remaining cards in your long suit, and they will always double you.

True.
Only, Murphies come in different flavors.

In the latter case,
(1) your pd will (should) be far less upset with you, than if you passed his forcing bid, and
(2) unless you employed some exotic standard for preempts, same thing will happen at other tables, too.

It's a very different kind of Murphy

[nullve]

Stuff that probably belongs in this thread:

After 1♣-(1♠) I've long been faking "system on" in the sense that

P = "0+, 4+ H" (same as 1♦ response without intervention)
...X = "same as 1♥ over 1♣-(P)-1♦-(P)"
...1N+ = "same as 1N+ over 1♣-(P)-1♦-(P)"
X = "0+, either 4+ D or bal." (same as 1♠ response without intervention) / "0+, 4+ S" (would have responded 1♥ without intervention)
...1N+ = same as 1N+ over 1♣-(P)-1♠-(P)
(...)

An obvious theoretical cost is that when Opener has a hand with which he would rebid

1♠ = rules of 19-27, either 4+S2-H5+C or 4144 / rules of 19-24, 31(54), 4054 or 4153 (see NOTE below)

over 1♣-(P)-1♦-(P), he will now have to find the least lie among, say,

X(NV) = "3+ H or 14-16 bal." / options on strong bal. hands (irrelevant here)
1N = NF Gazzilli: rules of 19-21, 2-H6+C / rules of 25-27, 2- H / 17-19 bal., 3- H
2♣ = rules of 22-24 ("13-15"), 2-H6+C.

But when Opener NV has, say, 10-12 hcp and 4153, none of these alternatives come even close to describing what he has. So in an attempt to solve this problem I've seriously considered both the silly-looking

a) 2♠(NV) = rules of 19-21, either 4054, 4144 or 4153,

which at least gets the range and shape across pretty well (but likely one level too high), and the spectacular

b) P(NV) = rules of 19-21, either 4054, 4144 or 4153,

which clearly invites disaster opposite an unlimited Responder. But, of course, there's a third possibility:

c) switch between a) and b) depending on the meaning of Advancer's pass.

A problem with c), of course, is that opps can't be expected to have meta-agreements covering

(1♣¹)-1♠-(P²)-?:

¹ rule of 19+, nat. / 14+ bal. (NV) / 10-15, either 3154, 4054 or 4153
² 0+, 4+ H,

so I also need to know what to do in case opps don't know what they're doing.

NOTE:

The idea behind opening 1♣ with 10-15 hcp and either 3154, 4054 or 4153 is, as I've touched upon in several other threads, two-fold:

• to free up the 2♣ rebid over 1♦-1M = 0+, 4+ OM
  
• avoid rebid problems over 1♦-1♠ = 0+, 4+ H when
  
  1N = "NF Gazzilli": rules of 19-21, either 2-H6+D or 2-H5D5C / rules of 25-27, 2- H
  2♣ = Gazzilli-like: rules of 22-24, either 2-H5D5C or 5S6+D / rules of 22-27, 3 H / rules of 28-30, any
  2♦ = rules of 22-24, 4-S2-H6+D
  (...).

[shevek]

W_N_E_S
P1 P2 P3 P4

1 natural pass
2 13+, any
3 could be a good hand (bids are obstructive)
4 near Yarborough

This has happened a few times, almost always successful for us, the strong passers.
Once I passed out with a flat 2-count to find opponents had 620.
Never tried this 3rd in hand opposite a 13+ pass in first seat. Seems less likely to gain.