First up its good to know the theory so you can start to prevent yourself from being exploited. However, it's also key to recognise you dont need to prevent yourself from being exploited by someone who isnt exploiting you.

Vs a guy who is 3betting 3% he has a leak in his game, we exploit that by adjusting the optimal strategy of defending a-1 and just fold a lot. Most villains are playing their own game and until he adjusts by 3betting more then just fold and don't 4bet bluff at all.

Something to consider is that Given the sizing we can consider set mining as our implied are higher and 9>3 should be okay to set mine vs a tight guy but the value of the ax hands isn't that good. Vs 10bb I'd just fold a lot.

The GTO style calc you used at the start is a strategy vs unknowns where we defend X percentage of range. However with reads our strategy and range should adjust with our opponents strategy.

Start by knowING some standard approximations of positional 3bets and defending ranges then defend them wider vs the loose guy and tighter vs the tight guy buy adding or removing the next best hands.

An example could be to consider if we really want to start 4bet bluffing blinds if positional 3bet is

< say 7%

I'm going to work on similar stuff myslef. The way I started out was looking at how often villain needs to defend to a 4b. Eg if we 4b (any frequency) to about 2.5x he needs to defend around 35%- on my phone and speaking from some recent basic study. Then we just look at villains likely defence range v our 4b and look at that as a % of his 3b. If it is lower than 35% then we can 4b a lil more. If it is higher we need to probably never 4b bluff.

Regarding if he 3b loads- we should probably just open less frequently so that we defend a decent ammount v him but our range is still quite strong. I fend to call and min raise a fair few flops if someone 3b a lot pre but isn't great post so in that instance we can defend a lot of suited stuff we can then raise bdfd/GS/2 pair.

How are you planning to approach this?

I'm going to work on similar stuff myslef. The way I started out was looking at how often villain needs to defend to a 4b. Eg if we 4b (any frequency) to about 2.5x he needs to defend around 35%- on my phone and speaking from some recent basic study. Then we just look at villains likely defence range v our 4b and look at that as a % of his 3b. If it is lower than 35% then we can 4b a lil more. If it is higher we need to probably never 4b bluff.

Regarding if he 3b loads- we should probably just open less frequently so that we defend a decent ammount v him but our range is still quite strong. I fend to call and min raise a fair few flops if someone 3b a lot pre but isn't great post so in that instance we can defend a lot of suited stuff we can then raise bdfd/GS/2 pair.

How are you planning to approach this?