[lamford]

 barmar, on 2017-March-02, 08:36, said:

You still need language in 46B4 to deal with what happens if dummy doesn't have any of these cards. Why declarer would say "win" when dummy is out of both the suit led and trumps escapes me, but I'm sure SB could find a way to turn it to his advantage.

I am happy with your interpretation of 46B4 as it stands when dummy cannot comply with the instruction, the same as when dummy does not have the card named. I don't think this causes a problem, but by all means suggest that something is added to 46B4.

[blackshoe]

How terrible would it be if Law 46B simply said "if declarer does not comply with Law 46A, his instruction to dummy is void and he must comply with Law 46A"? Yeah, there will be a lot of director calls for a while, but eventually even bridge players can change their ways.

[barmar]

I think there will be few director calls, because most players won't change their ways. You'll only get director calls from players who know about the change to the law, have changed their own style, and are willing to make an issue of it when the opponents continue the traditional designations. But I suspect that in 90% of cases, both sides use abbreviated designations, so no one will call the TD on either of them.