I didn't know the idea of 'double-tap and one to the brain' had a name ...
In my defense when I was in the Marines they were only just getting around to teaching Marines how to shoot the pistol in combat - and such training would be for the grunts first, REMFs last, and super-REMFs working for II MEF G6 last of all.
The Mozambique Drill (also known as the Failure Drill or 2+1 Drill) instructs the shooter to place a double-tap in the center of mass, followed by a carefully aimed head shot. The third shot should be aimed to destroy the brain, killing the target and thereby preventing the target from retaliating. It was added to the modern technique of gunfighting by Jeff Cooper based on the experience of one of his students, Mike Rousseau, while on duty in Mozambique. Rousseau was later killed in action in the Rhodesian War.
In my defense when I was in the Marines they were only just getting around to teaching Marines how to shoot the pistol in combat - and such training would be for the grunts first, REMFs last, and super-REMFs working for II MEF G6 last of all.