I, like many other beginners, have come to know the peril of TPTK. A few minutes ago in the BB with 1 limper and the SB completing I raise to 4x with AJ suited, and both call. Flop goes 7 J 3 rainbow. SB checks, I lead out with a PSB, UTG+1 calls, SB folds. Turn is another 3, another PSB, and another flat call. River is it doesn't matter, duh the guy had 33 for quads.

My question is: do we need to assume that guys are sitting on a set when they check/call on us when we have TPTK? I thought we bet for information, and I can't count the number of times I've stacked people with TPGK when I had TPTK. I know some alarm bells should be going off with the c/c but at what point is it self defeating to assume that? You could be good a good majority of the time and people are just floating looking to pair one of their hole cards.

Help?