To my mind MOT,s are a must have inspection for sure. But the system as been turned into a money maker by garages. years back I had a mini metro which failed its MOT on brake pipes, I took it to a 2nd MOT station who passed the pipes but failed it on bearings. I took it to the local taxi MOT station who passed it. As you will know the first two stations just wanted work, the taxi station did not undertake work. In France the MOT is for two years and is undertaken by MOT stations only. they don't do any repair work at all, in fact its very hard for them to fail a car on the day as they need to give you six months to repair any faults and if you have the same fault on the next MOT in two years you pay a 100 euro fine, unless its on immersions.
why any of you are using main dealers for anything bar warranty work beats me, find yourself a good garage and stick with them.F