I just retook the CCW class after letting my permit sit expired for way too long. One of the points the instructor made was when you get into a defensive situation your body won't let you close one eye to find the sights the way most people normally do, and that you should train to be able to shoot with both eyes open. This all seems to make sense, but my question is, in competitive shooting what do people do? One eye open? Both eyes open? Can any amount of one eyed shooting training overcome the body's defense mechanism to keep both eyes open in a truly dangerous situation?