Doyle's quote in SS I think is something like "Ask yourself, would I re raise here with QQ or less, if the answer is no you might lay them down".

I disagree with the above, I'm way more likely to fold this in a cash game than in a tourney. Tourney many hands less than AA make this play, here you have to think AA.

Tough lay down. I think the numbers are 1 in 20 times when you have KK someone will have AA, but don't quote me. Considering that it may be plus EV to never lay down KK... but again it's tough to figure out what other hand he could play like this. If you had raised coming in it would be one thing, but limp re raise screams I HAVE A BIG PAIR.