What if the artists who do the still shots got frame-by-frame stills of a sequence, edited each still, then strung them together again with the film's audio? It would work
Except that it wouldn't ;) It's one thing do a nice mock like Angel seems to spend most of his waking life doing, but even if he did do the same great job on each of a sequence, there's no guarantee it'll work. You can be a few pixels out with a mask on a still and it will go unnoticed, but if that mask shifts by another few pixels on the next frame, even if it still looks great by itself, the motion-detection bit of your brain will light up like a Christmas tree. It's a constant back-and-forth - adjust frame 2 to match frame 1, then you'll need to adjust frame 3 to match frame 4, only to find you can't maintain that into frame 4, so you have to go back through the frames again...
Oh, the fun I had with the head-bonking Stormtrooper and the bad projection of Alderaan...
DE