heart ace
Declarer either has long dia or long hearts. If they have
long diamonds (along with Kx of hearts) we need the red suits
to split in a way that will not allow declarer to toss enough
hearts on the diamonds to avoid 2 heart losers. That is asking
quite a bit though our club distribution increases the chances
of that holding from happening.
If declarer has long hearts the opening heart ace followed by
a heart might be the winner outright if p can ruff trick 2 and might
even be a winner if p has Q(x) of spades and dummy hits with AJ(xx) or
KJ(xx) of spades and a singleton heart (declarer might ruff with the top
spade and then lead the J intending to finesse p out of their supposed
Q(xx) of spades). Winning a trick with the trump TEN in the opps ten card
trump suit would rate to be a strong morale boosting experience
)))))))
Even odder if p has 2 hearts declarer might still ruff high and misguess
how to play spades figuring we would only lead the heart ace of we were
trying t give p a ruff (and they would be right about that anyway)