Worked at Eurocontrol's Maastricht UAC for 42 years and we, in Ops. were basically at the forefront of development of the ATC modern systems. From what I can remember, if the systems expert was on leave then nothing changed. If things went wrong and then we in the Ops Room worked around the problem and it went back to systems. But the basis was if there was a risk then wait. We had many successes and a few failures but we got round the problem through team work. That was in the 70's and 80's, great days. I think that BA is too big and splintered for that to happen, as can be seen from the result. Probably not the only organisation these days with this sort of problem... BT seems to be another case from my experience. There are too many managers, too much hierarchal mist and sludge and no ultimate responsibility.
It will be interesting to see what happens after the inquest.