Low Stakes 4! Sizing

In live poker, GTO sizing is usually thrown out the window with the initial raise and often with 3-bets, I don't see why we should necessarily follow it with 4-bets. Especially since in most lower-stakes live games it would be way too loose to 4-bet bluff as much as GTO recommends. If this is a typical 1/3 game, odds are that people are not 3! bluffing anywhere close to enough. Which suggests you should 4! less frequently. If you are 4! less frequently, your sizing should be larger theoretically.

When playing with a solver, there is always a direct relationship between size and how frequently you bet. The more frequently your range bets in a situation, the smaller the bet, the more rarely your range bets the larger your bet. When ranges aren't matching up to the GTO ranges, you should be adjusting your sizes in theory making it larger if your betting range is smaller and smaller if your betting range is larger than GTO. So there are plenty of theoretical reasons to 4! larger, more linear, and more rarely. I'm not sure you could ever get to 4x theoretically, but you can definitely get larger than 2-2.5x if you started putting in the passive $1/$3 players actual 3! range.

Exploitatively, a lot of Vs at $1/$2, $1/$3 will get overly sticky with many pps and scs that should easily find the muck. Yesterday I 4-bet QQ and got it in for about 150bb against QJs?!? (He won, but thanks anyway, let's play some more hands. Let me buy you a beer.) Last week I picked up AA and was $650 eff in a $1/$2 game, he 4-bet to $175, I 5-bet jammed and he called off. Never found out what he had but a K hit the flop and he mucked. My range in that spot is precisely AA. It wasn't a spewy game preflop and my move was certainly "wrong" from a GTO standpoint. And that's just what happened in the past week, I see it all the time.

If you are at one of those tables where 3!s are rare and are a strong indication that V loves their hand, they didn't 3! to fold. I bet obnoxiously big, those that will call with sometimes silly hands more than offset the few that will find a fold with JJ or AQ. If I'm against a V who 3!s frequently, I will adjust and 4! more frequently and closer to GTO. But I think it is safe to default to very large and aim to get about 1/3rd to 1/2 of Vs stack committed preflop because, with an SPR of 1 or less OTF, they will call/shove if they hit just the smallest piece of the flop.

When the reg 4bets to 200, it literally means he's never folding vs a 600 stack. Because he's committed with 33% of his stack already.
If he 4betted to 150 or less, he can still fold to a 5bet jam.

As for 110 as a 4bet size. I think it's way way too small, it's only 18.3% of his opponents stack, only 2.2x of the original 3bet. Live players call way way too much preflop. It's a mistake with whatever range he has.

I guess it's ok if you find the right opponents, ie. they 3bet light but will fold frequently to 4bets, you can do it with a polarized range.

I would have made it about 140, but found the play interesting.

Typically with 4bet sizing, you want to size it the biggest you can that still gets action. The reason “correct” sizing is so small (in my opinion) is because a good player is not going to give you action on a 4bet without being offered odds (and when they see you laying short odds to win the pot they will assume you could be throwing in bluffs, which is less likely the bigger the bet).

At LLSNL you are not playing against players who will react to your 4bet sizing this way. So you should very often be going bigger.