Wiz,
Thank you for your polite reply, my post was late and after a couple of large whiskeys!
The problem that the average FSO has is that they are not electrical engineers and therefore had to rely on what the trade was telling them about 'fail-safe.' Having finally applied sufficient grey matter, I now realise that this was not the case because the relays required to unlock the devices are generally maintained in an unenergised state. Loss of power does not always cause the devices to fail-safe. I personally was told on scores of occasions. "What's your problem? If all else breaks, they will 'fail-safe". At least allow me a degree of doubt. Should I now retrospectively revisit all those schemes and get them altered?
This confirms, the admittedly conservative approach, that belt and braces often is the safest way forward.
My real concern is that the 'sexy engineered and managed' approach is OK on paper but fails to take account of human nature a few years down the line or build in a degree of redundancy. The approach all too often seems to be, "we'll build it, maximising efficency and financial return, (single stair 40 storey buildings?) and then throw some clever stuff at it to make it appear safe."
The green box argument is just one example of how the design is not really fit for the purpose, (i.e. there are big security problems), but we can make it work if we chuck some gizmos at it and then cut a few corners.
Your reference to 'scum' members of society is the same argument that the government is using to systematically remove our rights as citizens. Attach a 'terrorist' label and we can get away with anything!
Regarding your road death analogy, see what happens to the law when a dozen people get locked into a single staircase (because of the entry control devices which are not fail safe), which is then compromised by smoke. We accept risk from cars and say, alcohol consumption because of the substantial benefits. Stopping someone peeing in the straircase, something that is entirely foreseeable at design stage, by compromising fire safety...isn't.