OK...
I got this one covered too...
Soooo....
You are sitting on the crapper peeing like a woman, probably with your pistol in temporary Hammock Carry Mode. When someone rushes your door driving it into your legs, confusing you and delaying your retrieval of the pistol that is no longer in the hammock position but now partially down a pants leg. With the luck you are having probably with the grip down and the barrel pointing up...
So yeah, a cramped stall with absolutely no room to maneuver makes much more sense than standing at a stall...
Maybe this is why my new office has nothing but single person restrooms.