Can we turn this question around ask it like this instead?
What percentage of villains do we give credit for outlevelling us and shoving with AA (or TT) here because they think we'll think they must be bluffing?
Or, what percentage of villains do we think are dumb enough to be "protecting" their AA by shoving on the mother of all dry flops?
I think that's the right question to ask.. But, villian would have to assume that HERO is capable of considering this line of logic. I'm positive that at this level this DOES happen quite often but I think this only happens when the opponents know that multi-level thinking is possible from their opponent AND to which caliber.
From what OP is stating, he hasn't been at the table long and thus, villian doesn't exactly have a solid read either. So how can villian know that using this logic is going to be profitable? When we don't know anything about new players don't we normally default to play more straight-forward?
Since the pot is already large after the flop, villian knows that ANY c-bet that's called is going to pot commit you anyways. So, in a sense, ANY bet he makes is the same as putting you AI.
So, if he c-bet with AK and gets called and bricks on turn, you are pot committed and he is drawing to 5 outs with only 1 card to come. Makes it harder to keep applying pressure.
So, why not keep applying pressure with the most fold
equity??? From villians eyes, we are near the money, if he loses, he's average stack, if you call with JJ, QQ, he has outs to become a big stack AND knock a player out. If he has something like AK, he definitely doesn't put you on KK+. So maybe he convinced himself that he has fold equity AND 5 outs if he gets called...
PLUS, if we are dealing with a crafty villian and he assumes that everyone at $500NL is capable of strong multi-level thinking, then maybe he shoves on a
bluff and assumes you are going to the exact logic you just went through, causing you to fold...? If we are going to give credit for villian shoving AA for the logic stated in this thread, we need to give thought of this possibillity happening.
EDIT: So, to answer the question above, I wouldn't give villian a HIGH percentage when we are dealing with unknowns. When we've observed play and we've played a few pots at this level, then increase the percentage.