Make sure he is not opening his eyes before the shot. If he learns to shoot this way, it can be very effective. When I used to shoot with both eyes open, I would shoot fine in a non stress environment. During a shot on deer, I missed a deer high and right. The next time I got a shot opportunity, I lined up the shot and then closed my left eye. Voila! When I closed my left eye, my sight picture was to the right of my intended target. What a break through for me!