[creamfillin]

I think Gelford summed it up nicely.

Positional aggressor - 3-bet
Unknown - I prefer call
Tightish-TAG player - Call CO raise, 3-bet button open

If I have 99 on KTxr board in a 3-bet pot and I get action I'm done with the hand. I think a more interesting situation would be if the flop came all rags like:

3s 5h 8c

Hero leads for 2/3rds pot
TAG calls

What's your plan for an overcard/brick on the turn?

Or how about a flop with an overcard and a flush-draw like:

4c 8s Qs

Hero leads for 2/3rds pot
TAG calls or raises...

plan for brick turn?