Probability question

[MathBabe]

I think you can get in a lot of trouble thinking of it this way. Yes, if you can see 3 aces on the board, logically nobody has AA. But that's eliminating possibilities, not calculating probabilities.

I disagree - it DOES matter what happens first. If the flop came first and had an Ace, then yes, the odds that anyone at the table is holding an Ace are mathematically less. But the fact that the hole cards are dealt first means that every person at the table has a 15% chance of being dealt at least one Ace, and you have to figure that into your decision-making.