Agreed, the electronic control system carefully controlled the acceleration rate of the engines, and the idea was to get take-off thrust as quickly as possible. I agree that at first sight it may look dramatic or even violent, but this was pefectly normal routine. (3, 2, 1, NOW!!....CLICK).
The 'off' position was of course NEVER used with the engine running; you had no control of the engine at all in this case, and the fuel and nozzle actuators were locked by a brake.
