Hi,

Let's focus on BB defense vs BTN 2.5x steal (6max, 100bb deep cash), after SB folded. BTN is a random / standard / pretty balanced player (not too loose, not too fishy, not too tight...) ; his stealing frequency is 45/50%.

Why should we 3bet hands like ATs, AJs, (any Axs in fact with kicker <Q), KJs, KQs?

I see many reasons for NOT 3betting :
- keeping weaker hands in Villain's range (dominated suited combos + dominated Ax and Kx)
- avoiding to fold vs 4bet bluffs
- avoiding to fold vs 4bet value hands against which we have 30+% equity (JJ, QQ...)

Also, here are some numbers from personal works :
ATs vs BTN 45% OPR = 61% Equity and an estimation of Equity Realization is 1.2
ATs vs BTN 55% OPR = 62% Equity and an estimation of Equity Realization is 1.32
ATs vs tight calling range vs 3B IP = 47% Equity and an estimation of Equity Realization is 1.1
ATs vs loose calling range vs 3B IP = 51% Equity and an estimation of Equity Realization is 1.1

If these numbers are correct, i guess this should lead us to just call with ATs in this spot, but :
1. most of the winning regs seem to 3B these hands (I just saw Innerpsy doing this with ATs for instance, and this inspired me this thread)
2. Snowie includes these hands in his 3betting range

So why 3betting with these hands in this spot?

To deny equity and make the pot bigger in case we win.

You should 3b in BB vs button wider than any other

Nowadays online its meta for tough grinders to raise min raise or 2.5x button when folded to them with almost any two cards. Its profitable just by stealing the blinds. At 500 zoom(majority of innerpsy's action) this is standard actually for almost all online cash game winning regs. Some more aggressive players will literally raise as weak as Q rag and J9 off on button. I'm sure if you have watched innerpsy play he does this also.

3B wider here to balance when you do have premiums and to exploit this type of loose open. Don't always 3B here with A10s etc but some of the times is profitable, especially vs weaker players who you think you have edge against post flop