Pretty much the same thing a couple of years later, just before I got out (woulda been worse, but I was a short-timer) it rained and my eyeglasses got all gooed up and I actually was a Non-Qual.
It was (1974-1978) 28-32 years ago for me (my how time flies) from boot camp to the final time I qualified with the rifle (M16A1 for me).
I always shot Sharpshooter, except my very last time I shot a Marksman (toilet seat). So my old khaki uniform shirt and green uniform coats now forever have a "toilet seat" on them.
I wore glasses myself, and had the problems associated with wearing glasses myself.
Just goes to show how these things could have worked out in real life I guess...
I could go postal if I continued to think much more about all of this..................
PS - in 1966, we qualified with M-14......I still want one, even tho I couldn't afford to feed it. Great piece of work, that weapon.