What range does tag have when he coldcalls 3bet oop???

I'd consider the heart of their range to be the top 5% of hands, minus the top 2.5% of hands: JJ/TT, AQs-ATs, KQs/KJs.

Hands that are a little worse (QJs/JTs, 99/88, AQo, etc) and hands that are a little better (QQ/AK) are the next most likely batch of hands, and then there's always a random smattering of hands they have no business having, like KK+ in one direction or lower SCs/PPs/broadways in the other.

I give a lot of deference to preflop cold callers, almost like they were in fact the raiser, but what exactly that means when you're IP and they've already checked is a little up in the air. I personally micro bet here, and this hand isn't a bad candidate for that as you'll often realize all the way to the river for very cheap, while denying a fair amount of equity from your opponents and remaining uncapped for if the runout/actions make you inclined to turn your hand into a bluff.

Even if you don't have micro-betting in your arsenal this can really go either way. You're like smack dab in the middle of your range (which should make you inclined to check), but you have good blockers against the type of hands that will call a big bet. If you're using a mixed strat with your range, it's gonna be a mistake to play all 16 combos of AK the same way anyway, so you probably just need to find a tie breaker based on (eg) tells.

i think id find a way to be all in

So...my first reaction is that being balanced with our raises would get thrown out the window if we have no raises at all, just flat calls or folds. We don't need to be balanced when our opponents are entirely unbalanced. We can just play exploitatively.

In this set-up, with V cold-calling the 3B from OOP, over an EP raise, and then calling our flop c-bet, next to act, and then donking a brick turn, I wouldn't be thrilled to raise for value with AA, much less raise as a bluff with AK.

If V check-called flop and turn, then donk led the river, we'd all say that's a super under-bluffed and nutted line. What's all that different here when he donks one street earlier on a brick? V's line actually looks pretty nutted.

I don't think this line from V is polarized, in the sense that he has a range of thick value and bluffs. I think his range has no bluffs, and it's mostly just thick value, not even showdown value. That's not a polar range, it's entirely linear.

What would his bluffs be? What combo cold-calls the 3B out of the BB pre, flats the c-bet next to act, and then donks the turn, on Q725rb, as a bluff? I can't think of one.

It just seems like wishful thinking to assign V a range that includes medium strength hands that will fold to a raise and also call a big river bet if the river is an A or K. The small donk sizing seems intended to induce a LAGgy response.

Against a "good" opponent I agree more with your line of thinking. Not necessarily the part where you said they won't have bluffs, but they're going to have a very strong range and any bluffs are going to be well thought out and probably limited in number. Against a good player I'm never raising when they donk into us here, I just call or fold.

The thing is a good player is never donk betting here. That is unless the initial post descriptions were way off to the extent that they viewed us as a maniac with a very weak 3-betting range and cbetting range to the extent that they have a large range advantage on the turn.

The OP describes his image as being a nit/tag, not a lag, so I don't know why his opponent would bet with a small size to induce a laggy response, as you suggested.

The small sizing is almost the entire reason I'm tempted to bluff raise here. It's not just our opponent's small $50 sizing I'm keying on. Our initial 3-bet size was also small as was our c-bet size. All these factors combined IME often contribute to villains showing up with some junk we wouldn't expect. I have seen similar lines where villains ended up showing down something like Q7o. When they make this small, scared looking donk bet on the turn I'm often calling BS.

Anyway as I've said before this is entirely player dependent. I already acknowledged before that based on the OP's description of this particular opponent I'm convinced his turn fold was the right play. So I'm not really arguing with you.

I'm just saying it's a big mistake to always fold by default against this type of donk bet. We need to be willing to fight back sometimes, whether by calling and playing rivers or raising.

This hand got stuck in my head, and I found myself thinking about it as I was driving. How we view it would seem to depend a lot on how we range V, and how straightforward we think he plays.

I think we can agree that he's not doing this with air, and it's really unlikely he picked up equity on the turn. I would think his range could be divided into a few buckets...

1. Nutted - QQ, maybe some slivers of 77

2. Blocking with SDV - 88-JJ

3. Bluffing / stop betting - AK

4. Thick value - AQ, maybe KQ

Whether or not we want to raise seems like it should come down to how often we think he folds 88-JJ and AK, and if we think he ever folds AQ/KQ. It also seems worth asking what our plan is for the river if he calls our raise, and we either brick out, or make TPTK.

My gut reaction to this was that we wouldn't have any raises for value or as a bluff, but I think I could see some logic to it, if we think there's a reasonable likelihood he's got better hands that will fold, or he'll pay us off with worse on an A or K river.

It's hard to see 88-JJ paying us off on the river if we raise now and bet again, but I suppose at that point it doesn't matter much, since we got our value on the turn. It's a disaster if we bet and he snaps us off with 2P+, so I wonder if we're not just checking back a lot, even when we improve.

It's hard for me to imagine a TAG-reg taking this line with any hand that isn't nutted, because all those hands hate being raised. But maybe that's the "balance" in his line - b/f most of his range, happily call our raise with the nutted portion. It just seems like b/f'ing is pretty MUBSy, when his line is likely to induce raises.

I dunno. We didn't get a reveal, so I guess we'll never know. It would be interesting to see some MDA for this line.