A friend just mentioned his eyes are changing and in recent years his left eye wants to take over. He has adapted by just closing his left eye before the shot, but he said he has to close it before the gun fully comes up, because if he's ready to shoot, sometimes he will find himself trying to line up on his left eye, and crossed up off target. This is for gun down casual bird hunting. It also seems to affect his bow and open sight rifle/pistol shooting, but making due so far, he says it sucks.