Zulu 10, it seems to me that we are all singing from the same hymn sheet, but perhaps from different verses. What you say as a designer is that you assume/depend upon a process of continuous review to ensure that your design was and remains in accordance with the airworthiness regulations. When you designed it you did so within the same regulatory constraints.
That in a nutshell is the system that worked for years, until the late 1980's, when VSO's set out to subvert it in order to balance their books. It has never recovered to this day. That is what has now to be attended to. It is not being resolved by the MAA or MAAIB, nor can it be until they are independent of the MOD and each other. That is the gist of this discussion.
Easy Street, there never was a "Golden Period". That cynical phrase comes from the H-C Report, itself a cynical misrepresentation of history. Any Aviation professional knows that "stuff happens", always did, always will. The point is, what do you do about it? What we did in the 60's was the RAF Flight Safety System and a beefing up of Airworthiness Provision. Avoidable accidents, so rife in the 50's, began to fall but never to zero of course. You do the best you can, and ensure a continuous feedback loop to try to do better. When that system was kicked in the teeth under the auspices of the RAF Chief Engineer, the whole process of continuous audit stopped working, and "stuff" started happening again with a vengeance!