OK, official break-down of last night. Examined car in daylight, found grease on the clutch pedal. He must have stepped in some in the garage sometime, and when he got in the car it made his foot slipp on the pedal. When his foot slipped that little bit, the clutch(a 4-puck racing job) grabbed and took off, throwing him off the pedal altogether. Byt the time he could get back on the brake and yank the key, it had already hit the garage.
God, what a mess.
And yes he did have his foot on the brake when he started it. But most people, like my brother, only use enough brake to keep the car from rolling under it'* own weight, which isn't nearly enought to hold the car against even an idling engine.