I suppose if you are pushing a car onto some punter you wouldn't, but I'd rather it was done properly.
Pushing what car on what punter, what on earth are you on about, i wouldnt in a million years bother with a snide MOT selling a car, whats the point? Do i look like i need to be ****ing people over for a few hundred quid.
Another point to make is this, see Kwik Fit for all their faults, i dont believe for one second that they fail cars that shouldnt fail, they might do a strict test, but a straight test it will be, why would they risk a multi million pound aspect of their business to try to fit you up for a few hundred quid?
They might try it on where there is no come back, ie you need a whole exhaust there love not just a back box, or you need performance tyres on that Corsa 1.1 mate, but with an MOT, not a chance.