Beamr,
I had left the Vulcan force when this accident occurred, but I knew the captain well. It happened a long way away with little resource on site for some time. I would not for a moment suggest that the investigation was in any way cursory but it was hampered by the time delay in getting RAF investigators to the scene. Factor in that this occurred nearly 50 years ago, investigation techniques were less well developed and that the aircraft carried no flight recorders and you will immediately see the difficulty in coming to a definitive conclusion.
As Timelord points out, this was an impromptu "display" and we cannot be entirely sure of the sequence of manoeuvres or the pilot's intentions. If you wish to try and understand how a large aircraft can be put in an unrecoverable situation in a display manoeuvre then I suggest that you read this report on the loss of
Nimrod XV239 at Toronto in 1995.
However I must emphasise that there is no way of knowing if this bears any relation to what happened at Glenview. The answer in that case is that we shall never know as the evidence wasn't there at the time and certainly won't be found now.
YS