tuc, like Nige I struggle to understand your posts, no reflection on you, for this is all far too familiar territory for you but unfamiliar to the rest of us. All the more reason you should persevere until we all get it into out thick skulls that 'they' have failed us all, consistently and continuously, in their duty to provide airworthy aircraft to HM Armed Forces. In truth it is all in your opening line:
The evidence is overwhelming that the MoD’s “robust airworthiness regulatory framework” isn’t actually implemented.
That one simple sentence is overwhelming and devastating in its indictment of the MOD. Never mind all the acronyms (like Nige I try and fail to put words to them, whatever they stand for they have one thing in common they do not do what it says on the tin!). The only solution is to make all of them subject to external regulation by an MAA. If they fail in their statutory obligations they are brought to book, publicly and painfully. Self regulation has served us badly over the years in Law Enforcement, the Legal and Medical Professions and Financial Services. But for sheer lethal effect nothing matches aviation for devastation when it goes wrong (well OK other than Nuclear Power). Military Aviation Airworthiness Regulation in the UK has gone wrong. It needs fixing, not patching, not papering over, but root and branch fixing without delay.