re: Poker & 3 betting on the button
As pokerkid points out, this is a very complicated discussion. Is the example a utg limp and a co raise? CO's range for raising should be pretty wide if it's a limp, and utg's range is fairly wide (that's why it's ok for co's range to be wide here) - if utg opens and co flats behind, utg's range is pretty strong and co's is weaker. Stats by position are useful here.
How often does utg fold to 3bets, how often does co fold to 3bets? How often does utg fold to cbets, how often does co fold to cbets?
Are we 3betting for value against players who will call with worse? Are we 3betting as a steal against players who will fold better hands either preflop or on the flop?
Here's a good article on 3betting: http://www.cardschat.com/f49/move-be...3-bets-133959/