[jk3a]

Let's make a couple of assumptions.
1. Opponent didn't float the flop. This should be pretty obvious because of the turn check.
2. Opponent rarely has a set. Again, because of the turn check.
3. Opponent would check down AJo/AJs/JTs on the river

Given these assumptions, let's assign a reasonable range to get to the river this way and then bet. {66-TT, QJs, QQ}

66-TT = 30 combos, QJs = 2 combos, QQ = 3 combos.

Let's say he only bluffs with 66-TT 50% of the time. He "should" have 66-TT ~85% of the time based on combos. Let's do an EV calc:

-65*15% + 201*85%*50% = $75

If my assumptions were true, folding is obv. a giant mistake. Let's skew them a bit and do another EV calc. Let's say he would check two pair/ or a set on the turn ~25% of the time. Let's also say that he would only bluff with 66-TT 30% of the time.

44/55/JJ/KK = 10 combos; KJs = 2 combos. 66-TT = 30; QJs = 2; QQ=3

-65*11% + -65*25%*50% + 201*64%*30% = $23


I think calling is clearly +EV. Someone please check these calcs. for me. Manipulate the assumptions as you like, but I think one would be hard pressed to prove to me that calling is -EV.