2/4 KK Ace falls on river.

[Aisthesis]

I really agree with you here, Ryan, but I see them do it all the time. More typical would be a QQ flat call, but I think if you make it $200, you're in too deep to give him credit for AA. I just can't bring myself to put in half my stack, then lay down to the final all-in.

Given the whole betting sequence, I really think this guy had AK or QQ/JJ(he's too tight to have had A8o, anyway, I think, but I also don't exclude something down to AJ, certainly not QQ or JJ), possibly also an AA that he was hoping you'd bet into. QQ/JJ also are still pretty realistic, as he may correctly figure the A to be a scare card.

What I really think the problem is with KK is getting into these muddled types of situations, and the only way to really avoid them is to decide very clearly PF what you're willing to give your opponent credit for. Then, if you're wrong, you're wrong, but if your worst mistake is getting it all-in PF on KK, then you really don't have too much to worry about (and I say this as someone who has thought a LOT lately about some alternative KK strategies).