Yep, Mark Wilson with his Glock lost against a guy with a rifle, but it wasn't the rifle/pistol dichotomy that resulted in Wilson's loss, but the fact that the bad guy was wearing body armor. Wilson shot the guy several times before the bad guy turned and shot Wilson. Unfortunately, most of the rounds hit the body armor.
True, it's not the rifle/pistol dichotomy, but the pistol/body armor one. My point was that the pistols that most CCW holders have on them are very limited in what they can do. So how can you know if this "crazed shooter" didn't come to the gun fight with the appropriate attire? Pistols are convenient to carry but I don't think they make good intervention weapons to step in an ongoing shoot out that doesn't seem to currently involve you.