Problem A leads to a question about BWS 2017. I quote:
"Exclusion Blackwood: When a call is defined as Exclusion Blackwood (EB), the replies are in steps similar to Key-Card Blackwood, but the replier does not count the ace of an excluded suit. The EB interpretation applies to certain jumps that name an excluded suit, and also when a player makes a slam-try, indicates a short suit, receives no encouragement, and then bids four notrump (in which case the indicated short suit is an excluded suit)."
Suppose. on the auction 1H-1S=4C-4D, I now bid 5C.
The paragraph lists two cases for understanding a call to be Exclusion:
The second one: "also when a player makes a slam-try, indicates a short suit, receives no encouragement, and then bids four notrump (in which case the indicated short suit is an excluded suit"
That clearly doesn't apply because it requires that I receive no encouragement and the 4D is encouragement.
Ok, how about the first one? " The EB interpretation applies to certain jumps that name an excluded suit "
Well, 5C over 4D is not a jump. But I did jump to 4C. Are they saying that because the 4C was a shortness showing bid hoping for slam that now 5C would be exclusion?
That interpretation sounds reasonable to me and would be useful here.
It's not certain that 7S is a make if partner has Kxxx in spades and the A of diamonds, but surely I want to stay out of 7 if he does not have that.
Suppose I bid 7S, the opponents lead a club, I rough. Lacking the spade J I do what? If spades are 3-2 I could draw trump but then I have four spade tricks, one rough, the diamond A, that comes to 6 tricks and I hopefully have 6 ore heart tricks. That's only 12.
So I could, at T2, come to hand with the D A and ruff a second club. and then what? If pard has the spade J I can play A of spades, overtake the Q of spades, hope for a 3-2 split, and hope hearts behave. That's a lot of hoping
Of course they might lead a trump against 7S. Maybe that would help pard get two ruffs. Maybe. T from board, J from Rho, K from declarer , maybe pard was dealt K98x,
Does partner need more that KJxx in spades and the diamond A to bid 4D over 4C? I don't think so. Of course he might well have more. It would be nice to bring him into the decision making prcess but how? He might not realize that Tx in hearts would be very useful.
But first things first. After my 4C splinter and the encouraging 4D, is 5C an exclusion key card ask? Seems reasonable. 4NT asks for keys, and 5C asks for keys outside of clubs.
I don't much play exclusion, mostly because it takes more when is it on/off discussion than I have given it. But can't avoid thinking about it here. Good morning exclusion, are you on today?
Hmm. I am starting to think 4H over 4D is right. Partner knows better than I do whether he has some extras, and if so he can bid 4NT and I can show my 2 keys and a void.