We apparently think a lot alike, given that I was ranging him the same way, and would have bet the same amount, if I was to bet (I think check-calling would be marginally better here, against most V's, and probably especially this V).

Hard to put him on AA/KK when he checks back the turn. But if we look at it from his perspective, and think like a TAG/ABC player, when we flat call pre in the straddle, we could have all sorts of nutted hands on this board. I can understand him playing pot control after we check-call his big flop c-bet.

I don't buy his story that he thought you were weak when he checked back turn. You called a 4x raise pre, and called his 3/4 pot c-bet. It sounds like he was scared of MUBs, and didn't want to admit it. Think about it - if he knew his hand was best, why not raise the river? He's playing tight, but also playing scared.

I wonder what he'd have bet if we'd checked river. More than $350? Less? Does he ever check back? I also wonder if he bets the same amount with worse Qx or JJ/TT. If he has sizing tells, or if he ever checks back AA/KK, I like checking the river even more. If not, and he's likely to be balanced when he bets bigger, I can see the merit in blocking for 2/3 pot.

Conceivably, we might go for thin value with 9x, or bluff with something like ATdd, and he might call with worse Qx, JJ, or TT. Even though you lost the hand, it seems well played regardless.

Nice to know you can size up with thick value in future spots like this, against this V. If you had 2P+, he's probably snapping you off if you go 1.5x pot.

is interesting. id never 3b pre but i do see the incentives rise as his open size gets larger. river strat seems to depend on his flop sizing / strat. if he goes big u want to go small as he is supposed to be polar, if he goes small u want to go big as hes depolar. blah blah.

think his turn x is ok, doesn't really seem like a 3 street hand even on brick runout so he wants to check somewhere (equilibrium seems to mix his hand ott if he chooses this flop size so i wouldnt overly read into what it does to his ranges)

ajss looks like a fold too in the history hand so idk maybe he just plays well (i get thats not expected, encouraged or even really allowed at home games but still)

If you're going to address me, please do it directly. The advice you get here isn't necessarily correct and you have no idea who is giving it. You could be taking advice that sounds good from someone who doesn't have a clue of what they're speaking of. Paying a professional given how much you're losing given the stakes is a far better option.