Sorry but dont understand the logic either...
An ITV certificate has no validity whatsoever on a UK reg car and if your UK MOT has expired, Gawd help you if you are involved in a crunch and the Traffico's get involved...you'll soon find out how (not) valid your insurance is!
As for 'rogue garages', I don't quite see where you are coming from...ITV certs are issued only by Government ITV Centres; garages dont come into the equation.
Unlike the UK, ITV Centres don't have an axe to grind; it matters not a jot to them whether the car passes or fails since they wont be the ones doing the repairs...
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