Sometimes it just doesn't pay to count

I encountered this hand last night. I was west in 6H after opening 1H and hearing 3C from north. North led Ace and 8 of clubs. Plan the play.

Dlr: Vul: Kx x xx AQT98xxx Q ATxxx K98xx Kx AJT9 KQJx AJTx x xxxxxx xxx Qx Jx

Basically the contract hinges on picking the diamond suit up for no losers. Obviously taking a straight spade finesse will work here as you'll get 3 pitches on the AJT of spades and then can ruff dummy's last 2 diamonds, but that's not a reasonable line of play. Given the preempt, south is a favorite to have diamond length. So, I think I'm going to eventually play the ace of diamonds and then finesse south for the Q. But to try to get more of a count of the hand, I decided to ruff a couple of spades in my hand. When the K fell on the 2nd round, I thought I had a whole count on the hand. North must be 2-1-3-7. So, after pulling the last trump, I cashed the king of diamonds and played low to the ten. No one else in middle Georgia would have found that line of play, but I am convinced it is correct. It just happens to be wrong when north preempts 3C on an 8 card suit.

As a side note, it would be the right play to play the K of spades from Kxx or Kxxx. North knows west's shape is 1-5-5-2 and setting up 2 spades can't possibly help declarer, so he might as well try to mislead declarer about his distribution in case there is a guess in diamonds.