"This makes me wonder what sort of stick the aircraft must have had for the part to fail?"
The aircraft still met section s so we know the flight must have exceeded the limits set out in the manual. I guess the which limits question can be answered by another look at the evidence but we will probably never know why.
The Civil case against the BMAA has the potential to put them out of business as I understand they are not insured in this case. I would guess a lot of effort will be put into looking at the real cause but it may be a long time before we find.
Rod1