The question as I understand it is:
Was the 2nd September loss of XV230 preventable, if so could reasonable steps have been taken to prevent the incident?
We don't have the full picture yet, we have lots of small pieces mainly in the form of FoI documents and reports, significantly the Qinetiq report and the BAE systems report. They may not make for pleasent reading for relatives, ground or air crew, but in the absence of the BoI and coroners inquest I would suggest that anyone who has seen these documents would be very hard pushed to argue that the 230 incident was not preventable.
The BoI but more importantly the coroners inquest are the missing pieces of the puzzle, the coroner must establish whether reasonable steps could have been taken to prevent the loss of XV230 and if they were not taken why not.