[jon_1van]

I think your 6th street check is clearly correct. Run a couple sims. You are rarely ahead. Granted I'm assuming someone already has 2 small pair. (99TT)

I think the check from the player recieving the Ace on 6th is a little suspicious. Most would bet that card, even if they didn't have the Ace. It would be very hard to raise the player who just spiked the Ace, unless you have him badly beaten. I'm guessing when a 20/40 player checks here, he is looking for the check raise...(or he should be playing with me in 2/4)