Maybe… but muzzle and finger would have prevented anyone getting shot, which is why they should come first and always.Do you think maybe being taught any firearm you haven't personally cleared is always loaded might have helped with that incorrect perception
Cooper's #1 applies even before you touch the gun, consider it loaded
#2 applies when you interact in any way with the firearm, never allow the muzzle to point at anything you don't want to shoot
#3 drills deeper into that interaction, even with the muzzle pointing in a desired direction, finger off the trigger until you decide to shoot
#4 Before you should be willing to fire, you should positively identify your target as the target and consider what or who will be impacted by a miss
And yes, the shooter “thought it was unloaded” which in his mind gave him permission to point at himself and others.