Originally Posted by sixfour
w/r imps. partner passes, rho bids 2nt, we do what with:
Could I have the spade jack please?
If we knew the bad guys were going to play in notrump we'd pass, but they probably won't.
If partner has nothing, meaning the opponents are probably making 4H (or maybe
even 3NT), then he will have no entries, and our well-located spade ten and diamond honors are in trouble. We will usually lose two spades, three diamonds, and a club, meaning that 4S is a good sacrifice at these colors, but only by a little (probably +3 IMPs). If the opponents aren't making game then we'll probably get another trick, but -300 will be a poor result in that case (-5 IMPs if they were stopping in a making partscore, -12 or so, iirc, if they were going to bid a failing game). If the spade jack doesn't take a trick against us we'll be +7 IMPs against their making game, probably +1 IMP against their partscore, and probably -5 IMPs against their failing game. Because we can't know about the diamond jack, what we have to think hardest about is whether their game, if they bid it, will make.
You have two very likely tricks (HA and DK) and one moderately likely one (in spades, with an honor, ruff, overruff, or trump promotion), particularly if RHO plays the hand (putting you on lead), plus a decent probability of a slow diamond, plus
anything partner can contribute. That's a high enough likelihood that the bad guys are going down that a sacrifice isn't a good deal. I think I want to let opps bid to their normal spot, then try to set them.
Against very aggressive opponents I would bid 4S, because I can add to the above calculation that LHO holding a stiff spade and about six of a round suit may bid to a failing five-level contract. But otherwise, I don't like the advance sacrifice much, nor a delayed sacrifice much more. Sacrificing against games that might fail, or might not get bid, is not a good thing.
[I admit that all it takes to make game is for partner to have a diamond honor, the spade jack not to beat us, and the long diamond either to score (when they are 3-3 or partner has the ten, for example) or be ruffable (which is unlikely against good defense). I may just be too pessimistic tonight.]