UI and AI

[Cyberyeti]

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?

He could have had both red suit kings.

 

He had A, xx, Kxx, AKJ10xxx

 

I had xxx, AQJ, AQx, Qxxx

 

And it rolled on the heart finesse. I picked my sample hand as it minimised the tricks we had off 6♠, there are plenty of hands where 7 is cold, either both Ks or an 8th club and a K or a 7411 with the K in the 4.

[c_corgi]

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.

[Cyberyeti]

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.

Partner had pretty much exactly what I decided he had when I decided to pass 6♣, 7 on a finesse.

 

We were 25 up in the match, and I decided 6♣ was more than likely a flat board, which I was happy with so I passed.

 

When 6♠ was bid, I decided the board was no longer flat and had to make a decision. The decision I made (wrongly) was that we weren't getting rich out of 6♠ but (correctly as it turned out) the odds of 7♣ succeeding had improved.

[c_corgi]

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.

[Cyberyeti]

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.

Your analysis is terrible:

 

Opps could easily have KJxxxx, xx, xxxxx, void opposite Qxx, Kxxxxx, xx, xx. This could be 800 and -11 IMPS, at best it's 1100 and -7 if we lead enough trumps.

 

I also thought it was possible partner was void in spades (we had no clear cut way to show this) at which point 6♠ can easily be 500 without a working red king.

 

It was always possible 7♣ was cold, but I didn't feel I had to take a gamble as I was not losing by playing 6♣, once I might have been losing on the board, I had to think about it much harder.

 

Worst case would have been void, Kxxx, x, AKJ0xxxx where we might be making 7 and only taking 300 with the K♦ in the hole.

[campboy]

I do not think the fact that he didn't bid grand the round before is very relevant. The argument for not adjusting is that the UI does not demonstrably suggest bidding grand; if that is the case it does not matter whether anything else is an LA.

[axman]

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.

 

Once it is accepted that N would not bid slam if he believed the partnership was off 2KC [while maybe bid slam off one] then once N bids slam then from S view [that the agreement was DOPE] he should** think that N believes South holds at least 2KC [as in S doesn't hold zero]. As such, it is not valid for S to assert that S has reason to KNOW some wheel has lost traction.

 

** S, looking at 2KC + CQ necessarily knows that N can hold at most 3KC

[c_corgi]

Your analysis is terrible:

 

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.

 

 

Opps could easily have KJxxxx, xx, xxxxx, void opposite Qxx, Kxxxxx, xx, xx. This could be 800 and -11 IMPS, at best it's 1100 and -7 if we lead enough trumps.

 

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?

 

I also thought it was possible partner was void in spades (we had no clear cut way to show this) at which point 6♠ can easily be 500 without a working red king.

 

It was always possible 7♣ was cold, but I didn't feel I had to take a gamble as I was not losing by playing 6♣, once I might have been losing on the board, I had to think about it much harder.

 

Worst case would have been void, Kxxx, x, AKJ0xxxx where we might be making 7 and only taking 300 with the K♦ in the hole.

 

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.

 

 

I do not think the fact that he didn't bid grand the round before is very relevant. The argument for not adjusting is that the UI does not demonstrably suggest bidding grand; if that is the case it does not matter whether anything else is an LA.

 

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.

[Cyberyeti]

Once it is accepted that N would not bid slam if he believed the partnership was off 2KC [while maybe bid slam off one] then once N bids slam then from S view [that the agreement was DOPE] he should** think that N believes South holds at least 2KC [as in S doesn't hold zero]. As such, it is not valid for S to assert that S has reason to KNOW some wheel has lost traction.

 

** S, looking at 2KC + CQ necessarily knows that N can hold at most 3KC

So you're telling us we don't actually play the system on our system card which clearly states that we sign off then partner bids 6 if we need the higher number of key cards.

[campboy]

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.

Either way all keycards are held. The difference the UI makes is that without it we must expect partner to have three keycards and a void, since he bid slam opposite none; with the UI he only needs the three keycards to bid slam opposite one.