Wow, Tuc, as ever a very informative and well-informed post. I wouldn't argue with anything you say there. However, (you knew that was coming, don't worry, just a perspective), from this pilot's point of view, I know there are imperfections in every system we are asked to operate and we could spend our lives trying to eliminate every gramme of risk from them. Personally, I accept a level of risk and understand the areas where a system (usually an aircraft, in my case) fall short of ideal, especially on operations.
Now, that is not to say that I do not (as I said) fully concur that the MoD has a huge duty of care. Quite rightly and this thread has highlighted numerous areas where they have, allegedly, fallen short. But there must be a balance and an acceptance by those that take the Queen's five pence that there is, at times, an element of risk, often due to budgetary constraints et al.
We could be in danger of regulating our aircraft out of the air or making new systems so expensive that we can no longer afford an air force.
I am playing devils advocate a little here, although I may be less risk averse than some. Bottom line for me is, yes, MoD's duty of care must be applied and enforced, but I would hate us to become so bound by regulation that it impedes our ability to get on with our job.
Reading this back, I may have slightly over-stated my case, but I hope you can see my point.