3bet Adjustments

[markuisis]

Sorry if there has already been a thread for this. Just a couple of questions:
1) What are you guys calling a 3bet from CO with facing a BTN 3bet from a TAG with a decent 3betting range? What are you 4betting for value?
2) Same question as above, except you are BTN or CO and one of the blinds 3bets you.
3) Finally, what are some typical adjustments you make when facing light 3bets? I can think of a few (4bet bluffing, tightening up a bit pf, maybe sometimes limping the BTN, calling in position lighter pf, stacking off on flop more liberally) any others?

thx