While guys always feel the need to "finish" the girl off after they just "got theirs", it's not always as satisfying. Some girls REALLY like that, others just want you to hurry up and get "back in the game". And no, it's NEVER ok to just get up after you're done when she's not, and run off to the bathroom, say "I'm getting a drink... brb" or go and watch tv until you feel the need "arise" again. lol Best thing to do is play with her a bit, talk a little dirty and try to get back into it as soon as possible. For most guys, they say "hey baby, do you think you can give me a bj to get it back up again...." (sometimes not exactly in those words... ). If she's cool with that and has done it before, then fine. But if not, be prepared for her to get dressed and leave the room asap. lol
So my answer in a nut shell is no. While it SEEMS like the right thing to do.. there isnt a man alive in America that hasn't already done this. lol Be original and think of another way to curl her toes while you're being a bench warmer.