Part of the test seems to be rocking the top of the wheel while it's on the ground. How hard are you supposed to do this?

I'm only asking because this test made an upper suspension arm balljoint knock/move when it wouldn't do it with the wheel in the air. When I tried it I got a very slight knock but only if I pushed and pulled the wheel in sequence. With the upper arm in my hand I'm getting the slightest bit of movement if I try very hard. While driving the car you couldn't notice it was worn at all and I've driven cars with worn ball joints before.

The guy who did the MOT is probably 6'2 20+stone and very strong, the ramp posts must have been rocking 2-3 inches at the top minimum. I'm just wondering if one of the smaller testers had done the same test whether it would have shown up the same.