Error in "A Guide to the Bridge Laws" - Duschek?
While reading -I came upon this paragraph in dealing with revokes regarding law 62C1-2. (Page 172)
"South leads a heart towards dummy's AQ3 preparing to finesse. But West, holding two small hearts, ruffs with the four of diamonds instead of following suit. South plays low from dummy, and East wins with the King of hearts. West discovers his revoke, and when it is corrected South can change his play from dummy. Since E-W are offending, South can Legally play the Ace of Hearts, dropping the King of Hearts"
Apart from starting a sentence with a conjunction, there would seem to be one inaccuracy and one piece of information omitted. (or a mistake).
The inaccuracy is stating that East "wins with the King of Hearts". At the point that East "Wins", West has already won the trick with his trump and playing the King doesn't affect that. The piece omitted is that East has the King of hearts singleton - otherwise why would he play the King on his partner's trick? if East has the King of Hearts covered then when South changes his heart from the three to the Ace, East can then change his King to another heart - after all that is what 62C2 says. (This was once not the case - Belladonna I believe got caught in a similar situation where the change was not allowed)
Am I missing something - or reading too much into it.
Comments
I think your analysis is correct – after the revoke is corrected, East is allowed to change to a low card after South changes to the Ace, assuming that East has a second heart available (unlikely after the King of Hearts play, but not guaranteed).
The King of Hearts then becomes a major penalty card (Law 62C2 / Law 50B), so declarer probably ends up eventually gaining the correct number of tricks regardless, playing the 3 to "drop" the King.
(This explains to me why East's played card can be changed after the revoke is corrected – given the penalty card, and the fact that the finesse was offside regardless, it's very hard for East to gain an advantage from doing so, so the law in question basically just prevents declarer getting a disproportionately large gain from a single revoke.)
I initially thought that Law 64C1 might absolutely prevent E/W gaining any advantage from the revoke by allowing the Director to adjust it away, but it applies only to established revokes, not corrected revokes. So I guess there might theoretically be some sort of deceptive play available as a consequence of partner's revoke being corrected. I can't think immediately of any position where it could happen, though, and even if there is one, it seems very unlikely to come up in practice.
(I guess Law 50E4 might theoretically apply, although it probably isn't supposed to? It seems intended to adjust for information from a penalty card that's used by the defender's partner, but it also seems to technically apply to misleading information from a penalty card that's used by declarer to declarer's detriment, even though this information is 100% AI even after the penalty card has been played.)
I've told Jacob about it and he said it had already been pointed out to him. He has his manuscript updated ready for a new edition in 2027!