[Redd]

[ QUOTE ]
I thought of another way to ask this... when are we considering ourselves only drawing to the turn and not to the river? Obviously a flush/straight draw is to the river.

[/ QUOTE ]

Yes, if want to know if you have the odds to call the flop and reevaluate on the turn (or call the turn and reevaluate on the river), then you should use the turn-river odds (in either case. The flop-turn odds are a little worse, but the difference is negligible).

You generally use the turn-river odds more often, to determine if you have the pot odds to call a bet (for instance, if you're drawing to a gutshot, and you need to know how big the pot should be for a +EV call). You usually only use the flop-river odds if you're calculating your pot equity to see if you can bet/raise for value (for instance, pumping a flush draw on the flop).

You sound like you've got the gyst of it.