Walter
I think you need to actually read what has been said on the airworthiness subject; not by me or anyone else here, but the Inspector of Flight Safety himself.
One need only recall Flt Lt Tapper took the extraordinary step of visiting a Design Authority to discuss RNS252 because the information he had wasn't good enough. That immaturity of the Aircraft Data Set should have been sufficient to raise red flags. He didn't trust the information he had, which is a serious Human Factors hazard. While the bare facts were reported by the BoI, they didn't take the next obvious step of asking why, and who had decided that Aircraft Publications should not be kept up to date.
The above is bad enough, but one must go further and ask what IFS said about the subject (APs) in his report. He confirmed not only were they not good enough, but the RAF used captured Argentinian APs to help maintain the aircraft. What an embarrassment and an indictment of the savings AMSO was ordering at the expense of safety. (Again, something notified by IFS, 17 years before Haddon-Cave said the same thing).
Quite a little gem that one, and for some reason not made public or, one assumes, known to the BoI, FAI, HCDC or HoL. (Or the Sun for that matter, who would have had a field day).
The scale of their use is irrelevant and IFS quite rightly doesn't expand on this aspect. The failure is so profound one need say no more in such a report except recommend investigation and corrective action - which IFS does.
At a higher level, it is a basic regulation that the APs authorised for use must be listed in the RTS. Neither the Mk1 or Mk2 RTS mentions these Argie pubs. At the very least, when notified of this by IFS, the Chief Engineer (Alcock) should have ordered a fleet inspection of the relevant components (IFS doesn't list them) and an urgent update of APs and maintenance procedures. If he did, it took years to achieve, and still wasn't correct on the day of the crash. But I'm sure he's explained all this to Lord Philip. And this is what Haddon-Cave called the Golden Period! I hope he's asked for a revised opinion on the evidence he was given by these senior staffs.