I am interested in Shaggy Sheep's last comment about being unimpressed by the accuracy/impartiality of an AAIB investigation.
As we all know, the AAIB has the duty to investigate all flying accidents, whether the aircraft involved has been a B747 or a Curry Wot.
My guess is that the people the AAIB would tend to recruit as investigators will mostly, if not all, have come from a background of 'professional' flying, such as the military or CAT.
Perhaps few of them will also be, or have been, ordinary flying club members and thus acquainted with private pilots or our kind of flying.
In my experience, 'professional' pilots not uncommonly regard the private pilot as a not very competent dabbler with minimal training whose skills are always going to be suspect.
If this attitude was to permeate the thinking of an AAIB investigation into a GA accident, it might have unfortunate consequences for the outcome of the investigation.
The impression I got, after reading the report and subsequently speaking to the inspector in order to express my complaint, is AAIB were pushed for resources and didn't check some stuff fed to them by the accident pilot (stuff the group had already seen from the accident pilot's legal advisors and which we had dismissed as a desperate attempt by them to reduce their client's uninsured losses resulting from the accident).
AAIB's hitherto excellent reputation sank beyond trace in my estimation following that episode. In hindsight, and since the comments in the report pointed a passing finger at me, the previous pilot to fly the aerolplane, I shouldn't have let the matter drop, and should have followed my phone call up with a written complaint and taken it further than that if need be. But I was very busy at the time and life's too short. It's something I still regret not doing, however, especially as AAIB had not contacted me at all to check the facts.