Frelon:-
are there any parallels to be drawn between the Air Cadet Gliding debacle and this?
Not directly Frelon, no. In your example it is alleged at least that the contractors reneged on their responsibility to abide by the regulations and build accordingly. In the case of UK Military Airworthiness the authority itself (aka the MOD) reneged on its responsibility to abide by the regulations, ordering them instead to be suborned and eventually to be largely done away with. Until that is acknowledged by the MAA then it remains part of the problem. What the contractors did faced with such subversion is a secondary consideration I would suggest.