Is it not true that never 4-betting is somewhat exploitable? Villain can 3bet w/o fear of getting 4bet. Could you not occasionally toss in an extra bet w/KQ otf for ballance? Notice that; as the villain checked the turn, it would have allowed KQ a free card (more expensive than never raising, but cheaper than calling a 3b/turn lead). To exploit that play villain now folds to 4bet unless he has odds to draw vs nuts (or near nuts). If villain makes that adjustment, he is now making an obviously highly exploitable play himself. How nice would it be if 4bet=win? You're 2bets would also get much more respect (or you'd steal a ton of pots) and you'd get a bunch of free cards.
Which, in turn would also automatically put your nut hands back into your <4bet range. Although, you would do that yourself by mixing up your play.
In fairness to lawdude; I believe his argument is that it is impossible for even very good players to have a perfectly balanced strategy. Furthermore; the better the player the more he will use hand reading to narrow his opponent's range. So, if you can charge him another bet in a way that will mislead him and possibly cost him more bets; that's a huge coup. Is it that big of a deal if it isn't balanced? Wait 10 years before you do it again...
As far as the metagame goes, playing a monster like this should slow your opponent down in future hands and possibly convince him to pay off future slowplays. I definitely don't think he wants us to always 4bet w/a set or even only 4bet w/a set. Lawdude is trying to exploit, he wants to win -- not cross his fingers hoping someone will screw up. You shouldn't veer too far off the theoretically perfect strategy, but if you're taking advantages of opponents mistakes and/or causing them; it's actually better than playing perfect. Are we really giving up 'playing' poker and going by a strict basic strategy like blackjack or video poker? If the opponent is truly un-exploitable we should take a walk until some drunks show up, or switch tables.
As far as the hand goes I think the villain still has AA, KK, JT, A(K,Q,J,T) FDs, KQ, 55 in his range. I'm not even going to mention the f word.
BTW -- I believe in what I wrote, but my questions are not at all rhetorical (except for the 4bet=win one

). If I'm totally wrong in my thinking please correct me.