You idiot!
Haha, obviously, it's a decent question, I'm kind of getting at the same thing. I'm assuming I have good flow as the engine hasn't broken apart.
My understanding (but then again I'm the one asking the questions here, too) is that having both is pretty ideal, but that pressure is merely that - a measure of backpressure. If you have maxed your flow at 50PSI but are running 80PSI, you just have a lot of packpressure in the system, which isn't necessarily great (not too bad either, I'd imagine at 80....maybe different at 120+).
And I would certainly be more concerned if my gauge suddenly pegged at 100PSI (it maxes there) than if it fell off to 20 pounds at speed. Either way, I'd be pulling over, but the first scenario would cause a greater sense of immediacy to me.
Just my $.01 (not worth 2 cents this time, since I don't know what the hell I'm talking about, really, just trying to use some common sense.)