1eyedjack, on 2014-June-16, 23:57, said:
Dummy can certainly object. It says so expressly in law 68D.
It would be unethical to accept the concession. But by the same token I have little sympathy for South.
Your lack of sympathy may be misplaced - we have no idea how experienced or how competent this declarer is. As you say, Law 68D tells us that anyone, including the former dummy, can object, and that the Director must be summoned immediately. He will apply Laws 70 and 71. Since there is no way West can avoid winning the twelfth trick, and then no way he can avoid leading a club,
and North will have the boss club at trick 13, declarer gets that trick. See Law 71C2.
Again as you say, Jack, the answer to "is it ethical" is no - Law 79A2 says "A player must not knowingly accept either the score for a trick that his side did not win or the concession of a trick that his opponents could not lose." So if dummy doesn't object to the concession,
West should do so - and call the Director. I know, I know. "What do we need the director for? We know what to do here." Maybe you do, but it's not your job, it's the director's job. What if you get it wrong? Maybe not this time, but some other time.
Note: In using "you" I'm not targeting anyone in particular, I'm using it as a general term.