I had an answer to Myrmidon's question typed up, but then realized I'd missed some stuff, and then some more stuff... it's a great hand. On serious reflection, I still don't know what's best, though I think most reasonable roads lead to about the same place
most of the time -- but there are important differences.
Assumptions:
- After the interference, your bidding is basically natural. It is reasonable to agree otherwise, but you probably haven't.
- Your opponents do not completely suck, so RHO's failure to open either 1H or 2H in third seat has meaning. Your opponents may be tricky and/or expert, but they probably aren't.
- Your partner can be trusted to realize that you are in an absolute game force, even though he is a passed hand.
- Your partner is thoughtful.
- You don't have any special keycard asks for diamonds (you should, by the way, but you probably don't).
Where do we want to go? Maybe 3NT, maybe 5D, maybe 6D. 7D requires a pretty specific hand for partner (heart void + club queen + [spade king or four to club jack], so you'll probably not find it. You can't find out everything you want to know, but you can find some of it. the most important piece of information is your partner's heart length, you should be able to find that.
What do we know about partner's hand? Five diamonds (rarely six). Probably the (wasted) diamond queen. Probably three or four spades. Short hearts, but how short is a mystery. One or two black honors -- RHO's overcall had to be in part for lead direction against a likely 3NT (it consumed no room, and LHO didn't open), so partner is rarely turning up with heart ace or king. 8-10 HCP -- if you open shapely 10-counts, then he has 8-9, because he does have a shapely enough hand to open (though his long suit is poor, but whatever).
What do we know about RHO's hand? He has (probably) five or six hearts (if he's doing this with xxxx AKJx x xxxx, then you shake his hand after the match and see whether he wants to play teams some time). He didn't open 1H in third seat, so he does not have
AK
A. Given that he has some shape (most of the time), he probably doesn't have
AK
K. (Check to see whether they play drury -- if not, he might have those cards.) He didn't open 2H, so he doesn't have six hearts or even a good five card suit (if he's aggressive) -- unless he also has four spades, which could easily the case. Almost certainly 7-10 HCP, but if it's 10 his black cards are soft -- maybe both black jacks. Not five spades, or he would have opened (something).
What do we know about LHO's hand? Little, but if he's decent he doesn't have seven spades -- a spade overcall of a strong club is too effective for him to have passed up, even with a yarborough -- and we also know he doesn't have a yarborough, he has 3-7 HCP, because that's what's left. He really shouldn't have six spades, though realistically he could if he's passive and the suit is weak.
That leaves at least seven spades between partner and RHO, with partner having at least three. That leaves four or five rounded cards. If it's two hearts, then the opponents have eight clubs, which is possible. Darn it.
Possible paths:
- Rebid 2NT. This shows the hearts, but nothing else. It will get you to spades (wrongly) occasionally, as when partner is 5=6 in the pointed suits. It will also wrongside notrump, and you could find yourself going down on a spade lead. You will miss slam almost always, and you will almost never get to a making 3NT instead of a failing 5D, when different paths wouldn't end up in the same place. Hence, this is the wrong call; don't do this.
- Double (if negative). Bad. Partner will often show his four-card spade suit, and you will not be able to talk him out of it in time. It also buys you nothing you couldn't get otherwise. Don't do this.
- Double (if penalty). Bad. Partner will sit, you are missing a very likely game, hearts is usually not going for 800, and even if it is you may be missing a slam. Don't do this.
- Bid 3D. Establishes trump. He will probably follow with 3H, you will bid 3S (showing a heart stopper, else you'd have bid 4C or 4D), and he can choose between 3NT (rightsided) or a diamond contract. Thsi is a reasonable path.
- Bid 3H. Establishes trump, sort of, while implicitly denying spades (assuming double would be negative), but what is partner to do over it? He doesn't stop hearts so he won't bid 3NT; he'll have to bid 3S with most hands, and when you then bid 3NT, what does he know? That auction shows doubt, often about the heart stopper. He may pull with a stiff heart, which is what you want; the problem is when he pulls with a small doubleton. It's also (barely) possible that RHO could double his 3S bid for a lead -- barely possible because his heart bid was for lead direction, and wanting a spade lead on the auction to that point gives him way too many honors. Meanwhile, if double would be penalty then this is Stayman-like, so after partner's 3S and your 3NT he won't often pull, and if he has only three spades you'll often miss 3NT when it's wrong to do. Bottom line: this is a reasonable call if double would be negative, a poor one if double would be penalty. I don't think it's best, though, because when you go slamming partner will often play the 3H as an advance control bid, i.e., the ace or king of hearts, and you don't want that.
- Pass. Partner will reopen (if he doesn't, get a new partner). If he doubles (meaning he often has four spades, but may be planning a prepared sequence), you deny spades by bidding 2NT, and he works out that you were looking for more -- with a slam-suitable hand he will often show you what's up with a heart control bid. If he bids 2S instead that's odd (and theoretically shows 5=6), but it almost certainly confirms a singleton or even void heart, and you are off to the races (possibly to a grand, as all he needs for that is a heart void, the spade ace, and either the spade king or the club queen). If he bids 2NT that's odd, and now I'd worry that the bad guys are beating 3NT in spades, but I can find out with a 3C bid -- doubt about spades should be clear soon, and notrump has been rightsided if he has something like Kxx Kx xxxxx Qxx. If he bids 3D you will wonder what the heck, but will try 3H -- he will probably bid 3S, you will bid 3NT, and maybe he will work out what's going on, and if he doesn't bid spades you can jump to 5D. If he bids 3C he is probably 3=1=5=4, and you can follow with 3D and see what he does -- you'll often stop in 3NT here.
Unfortunately, we don't know that 4NT is safe -- if partner has a single spade stopper, a spade shift at trick two may leave us with insufficient tricks -- so going beyond 3NT is wrong unless it's right, as it were.
Basically, we want to distinguish between:
- KJx xx Qxxxx Qxx -- 3NT is the only good contract;
- Qxx J Qxxxx QJx -- rare, but 5D makes and 3NT is down a fair amount of the time;
- Axx xx Qxxxx Qxx -- 3NT and 5D are each fine;
- KJxx x Qxxxx Qxx -- 3NT and 5D are each fine;
- Axxx x Qxxxx Qxx -- 6D is good;
- Axxx -- Qxxxx Qxxx -- 7D is good;
- KQxxx -- Qxxxxx Qx -- 6D is good;
- Axxxx -- Qxxxxx Qx -- 7D is good (and would be even better if the club queen were the spade king).
I think the best path starts with pass, and trusts partner to work out that passing, declining to bid spades, and only going 2NT, not 3NT, over his double, indicates interest in alternative contracts, and eventually he sees that you must be slam-suitable (thus holding good diamonds when you don't ask about his). Let's see how the above hands will go if we do that (yes, I know some of these sequences are non-trivial, but I'm trying to come up with our best chance):
- KJx xx Qxxxx Qxx:
- P - X
- 2NT - 3NT (correct result)
- Qxx J Qxxxx QJx
- P - X
- 2NT - 3S? (expressing doubt) or 3NT (oops)
- if 3S above, then 4C - 4D
- 5D - P (hooray -- but admittedly not easy)
- Axx xx Qxxxx Qxx
- P - X
- 2NT - 3NT? (or paths that get to 5D; correct regardless)
- KJxx x Qxxxx Qxx
- P - X
- 2NT - 3NT -- correct -- or pard may go beyond 3N, but you're still OK.
- Axxx x Qxxxx Qxx
- P - X? (or maybe 2S)
- 3D -- 3S
- 4C -- 4D
- then ace ask of otherwise get to 6D -- correct.
- If P - 2S, then
- 3D - 4H (splinter)
- 5C - 6D (correct)
- Axxx -- Qxxxx Qxxx
- P -- 2S?
- 3D -- 4H (splinter)
- 5C -- 5H (void)
- 6C -- 7D? (and if you only make it to six, you still at least push the board).
- KQxxx -- Qxxxxx Qx
- P -- 2S
- 3D -- 3S
- 4C -- 4D
- 4S -- 6D (correct)
- Axxxx -- Qxxxxx Qx
- P -- 2S
- 3D -- 3S
- 4C -- 4D
- 4S -- 5H
- 6C -- 7D (hooray).
On the other hand, if we start with 3D:
- KJx xx Qxxxx Qxx:
- 3D - 3S
- 3NT - P (correct)
- Qxx J Qxxxx QJx
- 3D - 3S? (probably)
- 3NT - P (whoops)
- Axx xx Qxxxx Qxx
- 3D - 3S
- 3NT - P (correct)
- KJxx x Qxxxx Qxx
- 3D - 3S
- 3NT - P (correct)
- Axxx x Qxxxx Qxx
- 3D - 3S
- 3NT - P? (oops), or maybe partner bids 4H at his second or third turn, but it's risky from his perspective.
- Axxx -- Qxxxx Qxxx
- 3D - 4H (splinter)
- 5C - 5H (void)
- 6C - 7D? 6S? (again, you may not make it beyond six, but that's OK)
- KQxxx -- Qxxxxx Qx
- 3D - 3S
- 3NT - 4S?
- 5C? - 5D (then you raise to 6D) or 5H (should be OK) or 6D (correct)
- Axxxx -- Qxxxxx Qx
- 3D - 3S
- 3NT - 4S
- 5C? - 5H
- 6C -- 6D? May well miss it the grand here.
Hence, I think passing is best. It leaves more room for partner to describe his hand, and on some of the possible hands he can hold, that extra room will pay off.