This is such an interesting post for me personally.
In the salon I cut then apply, but on the comp floor I usually apply then cut.
The acrylic doesn't shatter and it saves me faffing about with getting even application on the ends, (I just taper the acrylic application off, then cut with tip nippers and have a completely even layer with no thought or effort at all).
I have several trophies in this category and it really caught on here in AUS, when people were wondering what made my application faster and better.
I actually haven't done it for quite some time now ..... but now you mention it..... I think I'll have a play again with my next set.
I never shape my tips, I just chop them off and apply, it's kinda the same theory (that way I only shape once) ... at the end.
Nearly every file stroke effects the shape, I start at the cuticle area (eponichium) and work my way to the free-edge, (that's last).
My theory on this is the fact that a tree grows from the roots up, not from the leaves down!!!!!
As an experiment, next time you do a nail, count how many times you shape the free-edge ......