Sacrificing at IMPs (White on Red)

Yesterday I went over the potential outcomes when your table is in a 6 hearts that you think could/should make and you could bid 6 spades doubled which you're sure is going down at least 2 and possibly 4 (or even 5!) We were red and the opponents were white and sacrificing was right but only if we were sure partner had spades or diamonds or both to cover our non-Ace losers. Today we'll look at the same information but with the vulnerabilities switched.

IMP result if I pass 6 hearts.

tricks in S/H	4 or 5 hearts	5 spades doubled	6 hearts	6 spades doubled
10/12	-13	-16	0	-15
10/11	13	5	0	9
9/12	-13	-15	0	-14
9/11	13	9	0	12
8/12	-13	-14	0	-12
8/11	13	12	0	14

IMP result if I bid 6 spades (doubled).

tricks in S/H	4 or 5 hearts	5 spades doubled	6 hearts	6 spades doubled
10/12	9	-5	15	0
10/11	8	-5	-9	0
9/12	5	-5	14	0
9/11	4	-5	-12	0
8/12	-3	-7	12	0
8/11	-4	-7	-14	0

IMP gain by bidding 6 spades (doubled) compared to passing 6 hearts.

tricks in S/H	4 or 5 hearts	5 spades doubled	6 hearts	6 spades doubled
10/12	22	11	15	15
10/11	-5	-10	-9	-9
9/12	18	10	14	14
9/11	-9	-14	-12	-12
8/12	10	7	12	12
8/11	-17	-19	-14	-14

Our gain is better in every single cell of this table as opposed to the one from yesterday. We didn't include the down 5 option (possible if you can't take a single diamond trick) in either chart but it would have been an insane loser yesterday. Very bad if they were making and abysmal if they were going down in 6 hearts. On the flip side, today it would still be a positive move when they're making. (Pretty darn bad if they're going down, but at least if you're very sure they're making it's a good sac even at down 5.)

Perhaps the biggest difference comes when the other table stops in 4 or 5 hearts. Yesterday your loss when 6 didn't make was more than your gain when it did at all numbers of spade tricks. If you were going down 3 and the other table stopped short 6 hearts had to be making 19 of 22 times (86%) just to break even. On the other hand, the same situation with today's table only has to see 6 hearts make 9 of 27 times (33%) for the sac to be right.

A similar difference shows up when the other table stops in 5 spades doubled. Assuming down 3 again, bidding on yesterday was right if they had more than a 86% chance of making. Today it's right to bid on if they have more than a 58% chance of making.

This is something you can actually try to figure out. Are your teammates apt to miss their 26 point distributional slams? If so then saccing red on white is almost certainly going to be wrong. You need to be sure partner has the spades/diamonds you need to make it reasonable. Saccing white on red, on the other hand, has a lot of value. You need to be _really_ sure you're going to set them to let them sit in this 6 heart contract with wimpy/non-accurate teammates. There's no way with my hand that I can have any confidence of setting them more than 2/3rds chance of setting them, so if I doubt Andrew and Byung will find/get pushed into the slam, I need to sac this time.