Er,
You have to be a mechanic to move on to be an MOT tester, and there is no reason not to use all the rev range on an engine, as long as its in good condition and up to operating temperature. You cannot damage an engine by taking it up through its range, because after all this is what a guvernor is for... to prevent over revving...which you have fiddled with...
If you came into my MOT station with that attitude, I'd certainly fail you for the magic tree on the mirror, or the misaligned tyre valve, jut to be a c**k. If you came in, had a chat and it was clear that you were a car enthusiast, you'd be quite welcome to come under the ramp and I'd talk you through the entire test, warts and all.
What do you think of traffic wardens?