I support a practical test of operator competence / or a manufacturers course certificate, BUT I never understood why a 'blue card' could only be made permanent by attaching it to a vastly expensive NVQ which teaches you no more. Years ago a one week 'small crawler loader' course was selling like hot cakes at Bircham. Then an edict came out that 'all courses must be of two weeks duration' - so what did they do but combine the above course with a wheel loader course - the latter are in quarries - not much used in plant hire.
A much better combination would have been with the 1 week backhoe loader course, or better still leave things alone. Private students could not afford the new set up & student numbers fell away! Talk about snatching defeat out of the jaws of victory. I trained with JCB as an operator & never regretted it.
The USA system of a 3 day course on any machine type eg. Backhoe Loader, Dozer, (Federal Law - but does not apply to a farmer or self builder) seems much less beaurocratic & actually works.