Indeed I think it is not clear. It's an interesting hand.
We suppose that E is good enough to see the endplay coming. So, holding the
K, he must blank it. No choice. If he comes down to a club, a diamond, and two spades the declarer doesn't care who has the
K he simply leads a
, lets E take his club, and then claims. Just as you say, Todd.
So.. If E does not have the
K, say he has the J64, he should blank his 4. Declare is known to have exactly one trick in clubs, three in diamonds, three in hearts. If he gets two spade tricks, that's 9. What can E do about it? Nothing if declarer takes the finesse. But if he tosses the J6, then perhaps declarer decides that E has blanked his K, as surely(?) he would if he had been dealt KJ6.
I suppose really, holding J64, E should randomly pick one of the three as a stand-in for the K.
I haven't tried the Gibs on this but I think I will. With the given hand I am confident they would blank the K and I think it is likely they would randomly discard two spades if the had J74. So I think.
In which case the odds seem to be 4-3 in favor of the finesse. W started with four, E with three.
Angel's hands are always interesting. Here you have an extra clue of course. In one of his books, Kantar pointed out that finesses never work in quizzes!
Kantar also had one book where the first half was declarer play, the second half was defense play, and the hands were similar. Not usually the same, but similar. So maybe one hand would give E the Kxx, the other the Jxx.
One of the good features of Angel's hands is that they demonstrate that there is more to this game than appears at first glance.
For anyone reading this discussion who finds it overwhelming, let me say: The first time I ever saw, say, a squeeze described I thought "Who would ever do that? " Patience. I blew one of Angel's hands hand horribly . I thought it through correctly and then lost my focus carrying it out. The other I planned out and executed correctly. Conclusion: I don't always get it right, but thinking is better than not thinking.
On this hand there is a lesson for both offense and defense. Blank the K if you have it, blank a pseudo-K if you don't. If E blanked his K, declarer must go up with the A. If E blanked his pseudo-K, declarer must finesse. Make them guess.