A friend of mine was a Squadron Leader engineer who retired in 1995. I was showing him David Hill's excellent book, "Their Greatest Disgrace" which describes in great detail the failings of those VSO's. He was very surprised that he had never heard of one of the leading villians, ACM Michael Alcock, who was the RAF Chief Engineer, and his ultimate boss at the time. It does rather suggest that those VSO's kept themselves fairly remote from the coal face and this may help to explain why the ATC gliding got into the mess it is in.