Laws 16B and 73C
RHO opens 1NT. You overcall 2 !d on the understanding (this is a relatively unpractised partnership) that it shows both majors. Partner fails to alert. LHO asks anyway* and partner says it is natural. LHO doubles and this is passed back to you.
You have not discussed the implications of partner's pass of the double of a two-suited overcall, which is not really surprising given that partner does not think you are even playing a two-suited overcall in this position.
You have UI and you have two obligations:
(a) Under Law 73C, the subjective obligation to carefully avoid taking advantage; and
(b) Under Law 16B, the more objective obligation not to choose a call... that is demonstrably suggested over another if the other... is a logical alternative.
The definition of logical alternative in Law 16B1(b) includes the phrase "using the methods of the partnership". In this case the methods of the partnership are clearly, in David Burn's phrase "we don't know what we're doing". However, you are a sophisticated enough player to know that there are two mainstream schools of thought about partner's pass of the double in this sort of position:
(1) No preference between the majors. You are expected to bid your longer major, and pass will not be a LA whatever your diamond holding; or
(2) Showing diamonds, suggesting playing 2 !d doubled, either absolutely or opposite tolerance. In this case, pass may be a LA depending on your diamond holding.
Clearly, if you misinterpret partner's intentions you could get a silly result, but if partner intended (1) and you pass, assuming (2), you are likely to go for a large number, whereas if partner intended (2) and you pull to your longer major, assuming (1), you may not be in a very good spot, but you are less likely to be in a truly awful one.
If you really have nothing to go on as far as partner's intentions are concerned, are you allowed to take the safety play and pull to your longer major holding, say, a 5-4-3-1 hand with three cards in diamonds?
*As an aside LHO opened 1NT last night and partner overcalled 2 !c , natural. RHO looked at me quizzically, and I took pity on her and said "it's natural". "Well, I've _never_ heard of that!", she said (emphasis hers).
Comments
Logical alternatives aren't based on what your partnership actually does; they're based on what other people using the partnership's methods would do. So in this case, the question is "RHO opens 1NT, you bid 2!d to show the majors, LHO doubles, partner makes an undiscussed pass, RHO passes; what do you do?", and you need to work out what other people would do in that situation. If a reasonable proportion seriously consider passing, and some of them actually do, then it's a logical alternative. So this isn't a question about what the pass actually means, or what you'd hypothetically believe it means; it's a statistical question about what your peers would think it means, on average (and what sort of value they give to making a bi-bid of 2!s to handle both possible meanings).
For what it's worth, I can believe that a sufficiently small proportion of players would risk passing out an undiscussed call that's plausibly forcing, that pass may well not be a logical alternative. But I think you'd likely need a poll to find out.
I'm not sure that I agree. If you haven't discussed it, but you both play regularly with X, and you both play it the same way with X, then surely you are entitled to the benefit, and subject to the potential burden, of assuming an implicit agreement to that effect.
And if you think it's a toss-up as to how the pass is intended, it's a fair bet that your peers will think the same. Otherwise they wouldn't be your peers.
The UI clearly suggests that partner is taking the 2 !d call as natural and may not have a diamond suit himself. This demonstrably suggests taking some action - so provided you have diamond tolerance (3 small is perfect) then passing is definitely a logical alternative.
Regrettably when you know partner has misinterpreted your bid due to UI, then getting a silly result is very likely - if not at the table then via the TD.
I mean why can't partner be 1=2=6=4? (with LHO doubling for takeout and RHO holding AKQT)?
This reasoning seems wrong (although the conclusion may be right). Whether passing is a logical alternative or not has nothing to do with what's suggested by the UI, or indeed with whether any UI exists at all; it's something that's evaluated entirely in the abstract.
When making UI rulings, it's important that the "logical alternative" part of the ruling is completely independent of the actual UI itself; otherwise you can't hope to match the tests in the Laws. For example, the poll should be "what would you do here?" given a UI-free auction, and shouldn't contain any mention of the specific UI that was involved.
The only parts of a UI ruling where the actual UI itself is relevant at all are the "demonstrable suggestion" part (note: only actions demonstrably suggested over logical alternatives are adjusted away, which typically means that you have to work out the logical alternatives first, and then see which of them were less suggested than the actual action), and the "was there UI at all" part.
I totally accept that bidding is suggested over passing.
But surely what we are taught to do in assessing logical alternatives is to put ourselves in the position of a player with no UI. In other words we assume that partner knows we have both majors but has nonetheless passed the double. In those circumstances, if we had nothing to go on in deciding on the significance of partner's pass, it would be a safety play to assume that partner meant "no preference" and bid one's longer major. Not guaranteed to work, but with an improved chance of not going for a telephone number.
There is a world of difference between the unauthorised panicker who reasons: "partner doesn't realise I have the majors, heck, I'd better bid my better major", and the player who is trying to do the right thing under the Laws and reasons "if partner knew I had the majors, his pass might mean diamonds or it might mean no preference; if he had diamonds, maybe 2 !d doubled wouldn't have come back to me; besides, if I get it wrong I am less likely to get a completely stupid result if I bid my better major".
It is routine to adjust in the first case. I am quite comfortable if people consider that it is in principle right to adjust in the second. But I wasn't sure that it was quite so routine.
I don't think it's routine. And I think a poll along the lines of 'we haven't discussed what pass means here, do you stick or pull'' is entirely relevant.
I would also ask if there's been any discussion about 1D (natural) 2D overcall (majors) double Pass Pass.... is that asking us which our better major is, or trying to play in 2Dx?
Bidding is demonstrably suggested, everyone will agree.
What is unclear is whether pass is a LA.
Thank you. Very succinctly put (as always).