First and foremost. My condolences to the family of the two men. And to the great team that is the RNHA. They will be feeling pretty dreadful today, having lost a great pilot and a fitter who was an aviation 'nut.'
But...........to those who speculate and offer unsound opinions I would say one word, DON'T. You probably don't know what you are talking about since you were not on board, and every opinion is based upon pure specualtion. Only the BoI and the AAIB (yes they will be involved) will find the cause.
Having said that, read BEAgle's concise view, and as an ex display pilot I can assure you that he has it just about right.
I have my own view of it - as I expect does BEags - but like him it stays with me.