In some games one's ability to sneak past mobs depends in part on your level relative to the mobs, which means a level 1 likely has zero chance to sneak past, say, a level 10's back any better than they would if they weren't trying to 'sneak'.
My initial testing seems to indicate this game seems to use LOS so is it safe to assume you'll always manage to get past behind a mob (as long as you're outside detection range) no matter what level the mob is?
I've tried Googling this but most of the info comes from the early game and I believe there have been a few important changes since then so don't know if something I read from May '14 would still be valid.
BTW, this is query about PVE only.