When to make -EV plays that put opponents in tough spots

Question

Scenario: 9-hand SNG midway, with most players quite regular (no fishes, no professionals).

I raise 66 UTG+2 and get called by HJ. i CBet flop and continue turn for 2/3 pot each street, HJ calls both.

Board is Qh Ts 6h Qc 9h

I put HJ on Q by the turn, since he's unlikely to continue with draws on a paired board. I check the turn, HJ bets 2/3 pot, leaving about 1/2 pot behind. I contemplate jamming but nit-call. My rationale was, with all the draws hitting, a lone Q trips would not be calling a jam, since i can have any straight or flush or full-house. By jamming, i am likely only called by a better hand (QT, Q9, TT).

Assuming my thought process is true (which i know may not be), some players at the table did say that i should be jamming 66 there, since i would put Qx in a tough spot. The question is, is there value in putting people in tough spots even if its -EV (i.e. worse hands fold, better hands call)?

There was a similar scenario in a high roller event where (i think) Pratyush calls an open in position with 66s, checks back the flop, and fires the turn on a A T 7 3 2 rainbow board. He fires the river and gets called by a T, which is what he puts his opponent on. His rationale was that he didn't want a T to have an easy decision on the river, even though its almost always a call.

(apologies, the details on the hands are scarce because they are examples, as the focus on the question is on putting opponents in tough spots)

Answer 1

Never.

Your objective is to select the line with the highest EV. Full stop.

If you have strong reasons to believe that your particular opponent will make specific types of mistakes under certain lines and board runouts, then you can think about making exploitative adjustments.

Most (approximate) GTO solutions play a large fraction of hands with a mixed strategy. So, for example, if you know that your opponent tends to overfold on certain rivers, this will tend to break the degeneracy in favour of particular actions -- your exploitative solution is to select only one action instead of playing the mixed strategy.

But in this case, the exploit is the new highest EV line.

So, in general, first determine your best guess as to the approximate GTO solution for hand and action to this point. Then, if and only if you have strong reason to believe in specific deviations from optimality of either the player pool in general, or this opponent in particular, do you work out the best exploitative adjustment to make.

I think most players overdo this last step -- they tend to overgeneralize from very small sample sizes and go out of their way to "exploit" opponents who may not be deviating from optimality as much as they might think. But that might just be the Bayesian in me talking ...

Aside: Confining your exploitative adjustments to only those hands played with a mixed strategy also helps to camouflage what you're doing -- your opponent will need a large sample to detect that you are playing certain lines more frequently than you "should".

Answer 2

The problem here is that, if you think Qx is going to fold, then the spot does not appear tough to you! If you think only better hands will call your bet and only worse hands will fold, then you should not be making that bet! Why would you otherwise?

We could discuss, though, whether your assumption that he has Qx is always right, and whether or not it's true that Qx is only folding, but that's a different story