West might have played the Ace then the King of Hearts, supposedly showing more than two of them, on the grounds that there was no point in showing a doubleton without any trumps to ruff with.  On the other hand, picture East with ♠J9x and Declarer with ♠AKQ8xxx.  Now, assuming 2-1 trumps (the 78% case), Declarer will expect that he can afford to ruff the third Heart high.  So, West’s play could have worked with a different layout.

 East could certainly have done better by not playing the third round of Hearts, he knows for sure that he will score the setting trick with his ♠QJ3 unless something untoward happens.  But a suspicious Declarer, smelling a rat, will wonder why not.  If she gives E-W credit for not having a carding misunderstanding, and if she also credits East for actually being awake, then she might smell a rat and cross to Dummy for a double Spade finesse.  Declarer may be up to making that brave play, but the very least that East can do is put her to the test.