I am strongly left eye dominant and shoot everything right handed, including pistol although I can use my dominant eye while shooting pistol. It's not really an issue to shoot scoped rifles with my non-dominant eye, but shooting shotgun is a whole different ball of wax. I need to "squint" with my left eye to aim a shotgun. It took longer than it should have for me to become proficient with a shotgun because of that. Then I finally stopped aiming and started shooting instinctively, still shooting righthanded, but it's better than aiming. I'd say give your kid the advantage now by teaching him to shoot shotguns instinctively. My 16 yr old son had Mark out at Capitol City Sporting Clays as a shooting coach one year and he already is at least as "good" of a shotgunner as I am, and Mark teaches instinctive shooting using your dominant eye.