Well, the thing with locational on aliens is that for most (all but the tyrant?) alien classes the head isn't any higher than the rest of the body. As a result, what do you make be the "head" region? The front? There's no easy way to do it like with humans, where the game just calls it a headshot if it's in the top (some number)% of the hitbox.
is it a big problem if the program calculates with horizontal percentage instead of vertical?
ofc i can imagine that rear-front is more subjective than top-leg as the model is turning.
or lol, i can imagine a "turnbot", what instantly flips the model for the time of being hit, so headshots would automatically go into the assholes of the aliens. asshole bot. groove :-) (would work as bots are using teleport at q3 at the moment of firing a lethal shot)
even without a bot, i could imagine a charging tyrant who - seeing the luci shot coming - is rapidly turning the ass to the damage to avoid the headshot.
"have you seen opti's perfect 'assturn' at the last game? man, that dude just owns! I wish to make assturns as neat as him!!!" bsdakgjadsjkhHAHHAHAHA
so logical features can turn funny, watch out :-)