How often do ATC or anyone else report pilots to the CAA for the quality of their flying? Reading the AAIB report these reports were not MORs but something quite different. Am I right in thinking this is in fact very rare in the UK? If this is the case the clear inference is the pilot had been causing some genuine identifiable concerns. The same can be said for a flying school refusing a pilot the option to hire, in my experience you've got to be working very hard indeed to demonstrate that level of incompetence.
The affects of E are not proven either generally or specifically for this person but the willingness of the pilot to fly after taking it only strengthens my opinion that he had a know it all experimental listens to no one attitude and it eventually killed him.
Having seen at first hand the behaviour of some GA pilots I think revalidation through experience should be replaced with the LST or if revalidating outside experience then with a GST. Dare I say, in addition to this PPL examiners need to partial or fail pilots when required, rather than the "Pass with a b@ll@cking" I hear so often.