[James282]

Yes, he calculates the percent that the given hand will come in, and adds it like it was another card that gives you the best hand. For example, let's say you have AKs on a 49T board with 1 of your suit. You read your opponent for 1 pair, because he usually plays 1 pair this way. Normally you'd figure for about 6 outs, or about a 24 percent chance to win the hand. Since you'll make a flush about 5 percent of the time here, you can add about 1.5 outs to your calculation, because if you had 7.5 outs you figure you'd improve about 29 percent of the time by the river. Hope that helps, and good luck!
-James