Mot testers in northern ireland are trained chimps, most of whom are failed mechanics that couldnt replace a bulb properly without wrecking something, the mot is basically carried out by computers that you cant bargain with so the testers are glorified keyboard attendants that cant tell the difference between an antiroll bar droplink and a track rod end

its not a system you want introduced over there, also the system is ridden with dodgy testers that will quite happily accept monetary donations for blind eyes, passing your car using the previous cars test results. If i saw or heard an mot man revving my car anywere over 3000rpm i'd remove his right foot and feed him it. Also the smoke test for diesels was stopped a couple of years ago due to the amount of catastrophic engine failures and court cases. I'd hit them with a bill or a solicitors letter, it is negligence, they are supposed to be mechanics at the end of the day