I personally know of someone who was "passed" by the Vehicle Inspectorate to do Mot's and he was totally useless. Dave
An ex Service manager used to have this chap do "his" tests for him and then he would sign the certificates as if he had done the tests himself.
Someone "Grassed" him up to the ministry 
He was subsequently caught, but instead of getting banned for life he was given the option of sending this chap to a one day NT application course. Which he duly "Passed"
He then tested a trader's MK 1 escort and failed it on very minor items. When the trader returned a couple of days later I retested it and filled two pages worth of failures.
The trader appealed and when the vehicle was inpected by the Ministry I had to attend the inspection, I was asked by one of the Inspectors what my opinion of the whole affair was, I said to him that " he knew as well as I did that the chap in question shouldn't be anywhere near Mot testing" he replied that he knew that but it was "political" why this chap was initially allowed to test.
The other reason this service manager was grassed was because he used to do Mot's over the phone !!!!! he would "steal" certificates from the pad and write them out later for his "buddies" who used to ring him up and give him mileage, reg etc
