re: Poker & $25 NLHE Full Ring: QQ on a broadway board.
The villain is so tight, calling his re-raise preflop seems risky.
Then the flop. If he has AA, AQ, AK, KK, JJ, TT -- he's pretty happy. He doesn't particularly want to scare you off. So he bets less than pot. You are still there. He quietly rejoices. He's a little less comfortable with KJ, JT, other broadway cards -- but he doesn't have those, does he? He's too tight.
The turn gives him another K. The chances are high that this puts him in great shape, unless he has AA. With KJ, KT, JJ, TT, he has a boat. With AK, he has trips. With KK he has quads and is not worried in the least. He can check his boats and quads, hoping you hit something on the river. He checks his AA because he could. The river gives him the boat with the AA. He only bets half the pot in hopes that you hit something and will call. He doesn't have the royal, which is the only thing he's a little anxious about. He doesn't have a flush, either, so if he has Broadway with his AQ, that river would be uncomfortable -- hence the half-pot bet.
If you have him beat, I'd be really surprised. At best, it's a split.