No sight. I don't think he had eyes even, if he did we never saw them. Still made him wear a mask.
We tied him to another player with a 20 ft rope and kept a ref on him. He would listen, point his gun around, and the ref let him know if it was a ref or a player (He would point, follow a person moving, ask us if it was a ref or not.)
He loved it. He shot at people, and I can't remember if he got somebody, but I know he got close enough that his vision was as good as most 12yo's on the field. He hid, ran about, ducked when his bunker was hit. He had a total blast. He wanted to come back and work for us. I just about let him.
It isn't impossible, but unless the field is well ran, you has enough refs, and can figure out how to make it work, then it is a bit more crazy. It can be done.
But intuitively, no - of course, some people who are blind ride bikes. This guy was, short of being roped to another player and the extra ref, better then most teen newbies. That is saying something. Even blind he shot less refs...