[Acevader]

I remember I once incorrectly laid KK down preflop and villain turned over Q10o for a total bluff. I felt like such a spaz.

I also think friedace has a point about the positive selection. There is - understandably - a smug factor when you fold KK and a nit shows AA for whatever reason. However, the vast majority of the time you never see what villain is hiding and no matter how strongly you feel about it you can't be 100% sure he's always returning two aces to the deck.

Ironically the only way to get reliable data would be to deliberately felt KK when you would have otherwise folded it and record the hand villain had, the pot and the outcome. Now repeat many thousands of times (think how massive your overall hand sample would be for that!!!) and report back.