It's not really tightening up, it's adjusting. A lot of people in a pot usually means dead big cards. When you hit, you're only getting bad action or no action to the low pairs that missed their set. Same goes for 1 raiser.

Against raisers, you're on the call, so want a hand that you'll know postflop will be best or worst. In position, you want some semi-bluffing value. When you're worst, you get away cheaply. When you're best, you can stack the guy.

Counter that with holding QJ, hitting top pair with babies on the board and him betting into you. You'll win nothing more than the pot+his bet, get a raise called with the worst hand, or call down to find out you were dominated from the start.

I never bought the notion that big connectors play well multiway. You hit two pair and you have to be overprotective of straight draws, so you win small or lose big. You hit a straight draw, you're on the call. You hit a straight draw with overs and you have you see the turn and river with flop aggression. The free card play works with 78 to a board of K-5-6, but not with KQ to a board of J-T-2. Think of the ranges leading those flops. In the first case, you can win the pot with 8 hi, get knocked off a draw that you would've been knocked off on the turn anyway, or get a free card. In the second, you can almost never win the pot with K hi, trap yourself into playing a big pot with dead outs that'll cost you more, or hit your draw and not get another dime.

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