We were playing a hand in a pairs game at favorable vulnerability recently when we picked up a hand with six hearts headed by the KQJ and four spades with the ace and three little ones. Our left hand opponent (LHO) dealt and she opened a diamond. Our partner bid two spades indicating a weak hand with six spades. Our memory is cloudy but our right hand opponent bid three of a minor (diamonds or clubs).
The our analysis was right. We almost all the major cards, they have almost all the minor cards, they have enough points for a minor game, and being quality opponents they will bid it. They might even see the small slam that was obvious to us and bid that. Despite this good analysis, the hands revealed that we make ten spade tricks and they make 12 diamond tricks, we proceeded to make at least two and perhaps three wrong bids.
We passed on our first bid instead of bidding four spades. It was within the realm of possibility that it would get doubled and we make a top. It is more likely that LHO will bid five diamonds as she did. We should have bid five spades with our second bid after five diamonds but didn’t because we felt they would make six diamonds and we would force them to bid it. This was stupid. If five spades was a good sacrifice over a diamond game then six spades would be a better sacrifice over a diamond slam. Assuming the courtesy double (see ACBL scoring), we lose either 100 for down one doubled or 620 for a diamond game with an overtrick at the five level. So five spades was the right bid because we are 520 points better off. We lose 300 for down two doubled or 1370 for opponents making a small diamond at the six level. So if they bid six diamonds then six spades is the right bid. For novices at scoring, you get the tricks plus the game plus the slam to get to 1370.
We feel good about the analysis but really bad about the thinking.