It's a little bit slower, but I think it works best to ask if a roll is applicable here in OOC (or even just asking what roll you WOULD make to get a certain wanted result, or if there even IS a role you can possibly make)...and then roll when you get the confirmation. It keeps things relatively easy to keep track of.

[s]Plus, nothing is more disappointing than rolling a nat20 on a check you weren't supposed to make anyway, and it also eliminates that possibility xP[/s]

In fact, now that I think about it, maybe even attack and damage rolls should be done in OOC before a character's post is actually made, since combat can sometimes be very context sensitive. If your first strike downs a target, you're not gonna make a second strike on that target. And there might be nobody else in your range, so you need to do something else with your two remaining actions. Getting the flow of your turn ironed out before your post means you can now carry it out and flavor all of that however you want when you go to actually write your post, putting whatever little flourishes you want on the scene.