I'm not an engineer either, but I learned to drive in the 50's when both systems were around, the rear wheel brakes did a better job than the drive shaft parking brake. It was common to have brakes fail. And I remember several times trying to stop with the parking brake. Possibly the difference was that transmissions always leaked a little and the linings were oily. The best strategy when the brakes failed was to steer around what ever you were braking for.
