What do I do if a tiny eyelash is poking me? Should I just pluck it out?

Yes, pluck it out. If one, two, or three eyelashes are poking one in the eye, he can just pluck out the lashes. If he is not steady with his hands, he should have a steadier person do the plucking (wouldn't want him to accidentally poke himself in the eye). If the lashes keep growing back, he can ask an ophthalmologist to see if there is a way to fix the problem permanently.