EAP86
Good answer. Some years ago, during the Nimrod XV230 debates, it was asked what price MoD places on a life. I recall the formal answer was around £4M, which hadn't been adjusted for inflation in about 15 years. This was later reduced to just over £1M, which meant some proposed mitigations were not longer justifiable, in a financial sense. As you say, they were affordable, but didn't pass scrutiny. The problem, of course, is how to prove how many deaths this will prevent. (The Army got sucked down this path in the 90s and 00s, wasting years on studies and trials, while the solution was obvious and soldiers were dying. Government's facile response is "We're aware, we're doing something, these things take time"). It tends to lead to a reactive, not proactive, system; which is more to the liking of MoD and Government. For as long as I can remember, MoD's risk management strategy was "wait to see if it happens, then think about doing something". When something happens, people die.
This case is actually a very good example. How much would it have taken to avoid it? The regs existed which, if followed, would have avoided it. It cost more to not implement them. You can say the same for most accidents discussed here.