Playing it right the first time around

One of the ways I have been trying to improve my card play is to go through the deals in Fred Gitelman's Bridge Master 2000 program.  It is really good in that it moves key cards and opponents' distributions around so that if you make a suboptimal play, you will not be able to make the contract.

The problem, however, is that on lesson deals, one gets several chances to get the line right. Not so in real-life deals.  I would have appreciated a mulligan on this hand I played online.

How do you plan to make 4H after West leads the Ace of spades (presumably Ace from AK) and then switches to a club?

Suppose you were to test the hearts, and they turn out to be 3-2?  Now what?

I got lazy. After pulling 2 rounds of trumps and discovering the friendly lay of the suit, I pulled the outstanding trump and played diamonds from the top, planning to ruff out the queen and claim.  Can you see the hitch?

Yes, it's as if BBO had the spirit of Bridge Master.  East turned up with Q10xx in diamonds and the contract could no longer be made.  One line that works is to play 2 rounds of trump, play the Ace of diamonds to catch a potential singleton Q or 10 and then cross to dummy with a trump and finesse the Jack.

This was the complete deal: