Posted 2017-August-29, 13:56
Personally, I wouldn't pass at IMPs. There is too much that has to go right for passing to the be the correct bid:
1. Partner has to have exactly two spades. If he has one spade, 5D is likely odds-on. If he has 3, you probably belong in 4S.
2. Partner can't have strength outside diamonds. Then you belong in 3NT.
3. If 1 and 2 are correct, then the opponents have to find a spade lead.
This sort of parlay is not a good bet. And if you lose the bet, you lose 10 IMPs (600 at the other table vs your 130), whereas if you win the bet, you only win 6 big (+130 vs -100 for a gain of 230 or 6 IMPs).
I think 3S is reasonable. If partner bids 4D, I'll try 5D (and by the way, that might inhibit a spade lead). If partner bids 3NT, implying some outside strength, I'm happy. If partner raises spades, I'll hope he has 3 or else that the spades break.
And no, the opponents aren't going to balance holding only about 15 HCP between them.
Cheers,
Mike