c_corgi

I suppose the 5S bid is less clear in your auction than in OP, because in OP either/both 5C and 5S were likely to make, whereas in your auction 5C is unlikely to. Nevertheless, South has already shown great playing strength and North should cooperate with minimal values. Surely the amount you can obfuscate the bidding by giving misleading explanations is zero. If E/W really do have an agreement to add 3 points for a void or whatever in situations like this, as opposed to adding or subtracting a point or so depending on judgement, then it should be part of the explanation.

It sounds like inadequate disclosure, but I suspect the crux of the problem might be that West had a hand he did not know what to do with, decided to treat it as a GF raise and then tried to justify it afterwards. I don't think that there is damage because North (not South as suggested in OP) has a clear 5S bid irrespective of the explanation.

I wondered about this, but with such good diamonds I'm not sure it is so unreasonable. But I am curious as to how such possible actions are judged and what scores might be awarded depending on how plausible they are deemed.

You are quite right. I have never once successfully determined which opponent held a side suit king which my partner had already implied holding (or not needing) himself. If the distribution is so extreme, is it not possible that teammates have found the save as well? Would the West hand not save if he had QJxxxx xx Kxxxx void? Crikey, that does not look like a suitable hand to ask for KC to me, but each to their own. What would 4C, 4H, 4S and 4NT mean on the hypothetical occasions when partner does not wish to employ kickback? Is it really out of the question that opponents may have bid grand themselves? They are, after all, chasing the same defecit you are protecting. Furthermore they might have opened a Benji 2C or something, leading to a more agressive auction. Waiting till UI has been received before thinking about the problem harder is going to lead to adverse adjustments. The UI demonstrably suggests that all the Keycards are held, which in turn demonstrably suggests bidding grand. This information is pleasantly reassuring in an auction where the wrong number of KC have been shown.

If you are so confident that partner will have the hand he turned up with then 6SX with the king of hearts placed well for you is likely 1400 (1100 at worst), so you are still in a position to take the money if you expect 6C to be the contract at the other table. If, on the other hand, you expect 6SX to be cheap, that implies that either 7C was always cold or the red king is well placed for them. In neither of these cases is pass followed by 7C attractive.

That is precisely the point. If there is no keycard off it, then grand is virtually guaranteed with your hand over 6C. Partner being rather light is the only reason it needs a finesse. Having not bid it over 6C, I cannot see how you expect the result to stand when you bid it later with UI.

That looks like a very reasonable hand to expect from partner (given that he thinks you have one ace). It would be an excellent reason to bid 7C over 6C. No red suit finesse is required to make grand (as with many plausible hands he could hold), so the inference that it is more likely to work is irrelevant even if it is valid. What were the two full hands by the way?

If you demonstrate the first there is still UI, but now there is also AI that points to the same conclusion. You had that AI when you passed over 6C, so you need to demonstrate a conclusive reason why AI now removes LA's to 7C over 6SX. The onus is on you to do so because otherwise it looks as though all that has changed since the pass of 6C is that UI has confirmed that your suspicions were correct when you were not prepared to back them before.

You need to demonstrate that partner taking you for one KC is the only possible thing that could have happened. I remain unconvinced that partner could not have dispensed with/forgotten about the "sign off if you need 2 rather than zero" agreement. After all, he has asked for KC when holding an uncontrolled side suit, which carries with it a suggestion of maverick tendencies. You also need to demonstrate that your inference regarding the red suit finesse is (a) valid and (b) substantially affects the chance of success in 7C.

OK. So onto the UI issues. Initially South passed 6C because he knew something had gone wrong and didnt know what. The UI available by his next turn told him that what had gone wrong was that North thought that they were off precisely one KC because he thinks South has precisely one in his hand. South has a huge hand, so knowing the presence of all the KC (and presumably 2nd round red suit controls) makes it a fairly clear 7 bid IMO (but no more so than on the previous round), but knowledge that all the keycards are held is UI. If the reason South passed over 6C was cold feet and the UI warmed them up that is still UI.

We are at cross-purposes. We know North thinks South has 1 KC, but the problem must be examined from South's perspective. South has no AI to tell him his partner expects 1KC: he thinks North expects 0 or 2. He is contending that North bidding slam implies that North is placing the contract on the basis of his partner having zero KC, which obviously implies a misunderstanding. I am contending that North bidding slam does not imply that he expects his partner to have zero rather than 2 KC.

Surely failing to save over 3NT cannot be construed as other than fielding?

I don't think this is clearcut. North may have inferred or guessed that South had two KC. South's argument that he passed 6C because of an expected losing finesse is also unconvincing. North has asked for KC and bid slam facing 0/2 and a potential 9 count without caring about the QC. He presumably holds a very powerful hand with long clubs and 2nd round control in both red suits, so there is unlikely to be an issue regarding location of a red king. It is possible that AQ opposite a singleton needs to play for 2 tricks to make the 13th, but much more likely that there are simply 13 on top (assuming no missing KC). The additional information from the 6S bid only applies to (rare IMO) cases where the finesse was needed for the 13th trick and all it does is increase the chances of the finnesse working from a figure that is around 50% to one that is a bit larger. I think the only tangible reason for South to change his mind regarding whether a grand is on is the UI that clarifies what partner was doing.

Despit North's failure to make a grand slam try over 4S, South has a ridiculously good hand over the forcing pass of 6S. But why has North not doubled 6S if he thinks they are off a keycard? It seems far-fetched for this to be an attempt to play 6NT (especially since he presumably has the Ace of Spades himself) and it seems likely that it could have been induced by UI or CPU.

I agree with BunnyGo, it sounds like dummy has revoked. The revoke is established and cannot be unwound. But surely the suit to follow for the trick is determined by the card played (called) by declarer, not the revoke by dummy, i.e. dummy and a defender both revoked, so there is no rectification (L64B7). Play continues. If law 45 is interpreted so that the card deemed to have been 'contributed' by dummy is the card called by declarer, and it is deedmed to take precedence over law 61, then it will inevitably lead to the same card being played to more than one trick, thereby invoking L12A2 as suggested by Xiaolongnu.

I think this is because most people feel that it is not worth trying to find out if opener's hand is so unsuitable as make game a poor proposition, but are happy to punt facing the slenderest of 1♠ openings. But most people also do not feel 3♣ is a wise choice. Those who do, such as present an argument that was not put forward by East and should therefore be discounted. Or that essentially East was trying to play 3C as something along the lines of '2-way: a mixed raise OR a second tier splinter', the advocates of which, such as and warn against trying to introduce it without partnership agreement and the methods to procede accurately. The fact that OP does not mention such methods suggests that they don't exist, as does West's lack of wariness about making a slow signoff. Yet OP speaks of a high level of play, so we must determine whether East has made a surprisingly negative evaluation or chosen what seems like a misguided masterminding strategy. Knowledge of East's habits might help resolve this, but it feels as though if in doubt the director should rule against East, who may be successful in appeal.

The laws seem rather vague. Can we rule that no revoke has occurred, designate both pairs as the NOS and award an artificial score that protects the equity of both sides following the irregularity?

It is not clear from the OP that playing the 9 is irrational. If there is nowhere else to look for the 12th trick, declarer may have to judge whether LHO has underled the Ace or the Jack-Ten.

3D then overruling partners signoff is sufficiently analagous to East's action that they can be considered his peers. In fact there is more reason to bid game after you showed 7-9HCP than if you already showed 10-11. It is no surprise that consulting peers produced a silly answer here.

Very likely you will, but that does not make it right for a player who bids illogically to be protected by the (arguable) absence of an LA.

Sorry, I misunderstood. But clear now :)

No doubt you are right, but it feels very wrong that a player can make a limit bid and then overrule partner's decision when in receipt of UI if his "peers" are unanimous that there is no LA. Surely it would be better if we only had to poll in unclear cases.

North admits they are playing 1430, so there is definite misinformation. If North thinks that 1430 means 5D shows 1or4 then it explains why they keep bidding slams holding the wrong number of aces; it does not explain why he played partner for 2or3 keycards. We need to know why North bid a slam off 2 keycards if 5D shows only 1. I am not sure why East should have to guess whether South has not got his 1NT bid or his response to Blackwood. The latter seems like an unusual psyche.

Are you sure the auction is correct? If so, West should not have been on lead and I am curious regarding the meaning of 3H and 4S. Also, if North is responding to RKCB then 5S would be the normal response, not 5 of either minor.

Leaving aside the debate about N/S disclosure, the existence of which bemuses me, is there any evidence to suggest damage, apart from self-serving statements by E/W? The only logical way I can see to interpret their actions is that W doubled 4C to show clubs and East cuebid North's suit as a raise of clubs. This would imply that East at least had understood the explanation.