SMN Battle Mechanics

Notice Cait Sith’s model on the first one? He hunches down on the first one when the AC animation obscures the first BP animation. However you can still see the end of the first animation after the AC animation clears. Another good indication that the first BP has gone off is that the mob turns on the first frame of the BP.

Edit:
Slowed it down for easier counting.

This. Not only that, it resets your BP timer. So it's better to have your BP timer down when you pop Conduit anyway, might as well burn Apogee as well and get that timer counting down.

Also, when your Conduit ends your BP timer will usually be down. So if you want until afterward to pop Apogee, you're probably going to be sitting there for 20 seconds waiting for your BP timer to be up again before you can actually use Apogee. (Or waiting for Wild Card / Random Deal.) Mechanically it just seems easier to me to use Apogee beforehand.

Unless, like Frod alluded to, there's a strict time limit like possibly Schah. Although honestly, even with Schah I open with Apogee because there's plenty of time for it. I save the Super Revit for after Conduit wears though. I don't want to spend too much time fooling around before burning the main engine because it just increases the possibility for things to go wrong (like your avatar dying).

there's avatar death and things like around the 45s mark where he'll do a potentially debilitating TP move. It really comes down to "are the weaker apogee hits worth risking the tail end of full power conduit hits?"

Yes