Quote Originally Posted by jyms
1% or there about will never be the determining factor of calling a bet or not. The 2 and 4 rule is standard. What most people fail to learn is that the 4 is only good if you plan on seeing both streets for the same price.
Also remember you often have "outs to outs." Example: Hero holds TT on a 983 flop. Even if Hero is worried about an over pair, he has 8 outs to an OESD (16% chance) after the turn. This is NOT the case with a 986 flop where Hero's set might make Villain's straight.

It's important to put villain on some kind of range when doing this, but Hero should think about which cards left in the deck are "good" and "bad" and which are "blanks" (no likely help to either Hero or Villain). Often a mediocre hand that is likely behind on the flop will have enough "good" cards left in the deck to make continuing worthwhile. Depends on villain, action, stack sizes, reads and other things, of course. But it's often correct to "get out ahead" of a hand when Hero has lots of good cards (12+) that will make a strong draw on top of the current holding. Fold equity plus the outs often make aggression the proper play.

When thinking this way, use the x2 rule to determine probabilities, reads to determine fold equity, and good judgment to decide how to play it.