We all know 3B or Fold is a popular simplification for all positions except BB,
but I haven't heard much about simplifying to 4B or Fold.
Could this be a viable simplification, especially when OOP?
I ran some quick sims that seems to suggest it could be a pretty reasonable simpflication.
CO vs BTN 3B (BTN playing 3B or Fold)
EV with calls: 16.4bb/100
EV 4B or Fold: 16.4bb/100
Strategy changes: CO opens slightly tighter (28% vs 30%), BTN 3bets wider (15.7% vs 13.8%), CO 4bets wider (8.1% range vs 6.1% range)
What if we nodelock BTN to 3B the same range as vs normal GTO (13.8%)?
Strategy changes: Open our normal GTO range (30%) again, 4Bet 7.1%
**********************
SB vs BB
EV with calls: -25.7bb/100
EV 4B or Fold: -27bb/100
Strategy changes: Again we open tighter (39% vs 45%), BB calls tighter (34% vs 36%), BB 3bets wider (21% vs 19%), SB 4bets wider (12.9% range vs 9.7% range)
So here, in a wider formation, we are losing significant EV if BB max exploits us.
What if we node-lock BB to play normal GTO calling and 3b ranges?
We are still losing significant EV (-26.8bb/100)...
**********************
Conclusion: 4B/Fold is probably a fine simplification in all formations where we 4B OOP, except in SB vs BB where 4B/Fold would probably sacrifice too much EV to be a good strategy.
What do you think about about 4B/Fold as a simplification?
And what is the reason SB vs BB loses more EV when simplifying to 4B/Fold? Wider ranges? BB 3betting a more polarized range?