Exactly.
Autos are much easier to play with right at the balance point- by left foot braking you can preload the suspension to get the car into the worst possible angle with the wheels stationary, then by backing off the brake the car actually "relaxes" as it moves, reducing the angle and making pretty crazy lines driveable.
With a manual, the car always winds up as it moves off, which contributes to the instability.
"Coughing" from the carby stumbling can be enough to send a car over too.
"Hopping" is another big problem on climbs where you have to stay on the power. It's one of the reasons I'm such a fan of my radius arm/coil setup - it NEVER hops. Between that, 120:1 gearing and a line locker, I can drive my car onto its side on every trip with the best of them
Steve.