That's because the M68 Aimpoint is a combat optic DESIGNED to be shot with both eyes open. If it were a SCOPE, then yeah, shoot it with one eye. And move it closer to the rear sight. But because it's a SIGHT, and designed to be shot with both eyes open, the (arguably) *correct* placement is flush with the rail on the upper (on a stock upper of course).
- the know nothing guy who's a certified instructor by the military to teach this shit to the military
My two pennies. I do see the advantage with a magnifier to move the whole unit more towards the rear sight. Aimpoint alone, flush with the end of the rail on a stock upper, which is about where he has his.