jayteeto,
Thanks for that.
Just remember that the requirement was that Reviewing Officers be in no doubt that negligence was a cause (although not necessarily the sole cause) of the accident.
Para 23 from the final submission to the HOL Committee:-
"What is clear is that at some point the aircraft entered cloud, which the pilots had been warned to expect, and that it did so well below safety altitude, at high speed and heading for high ground. As they approached land the pilots should have been aware that their visibility was about to reduce significantly. The finding of negligence is based on the incontrovertible fact that they failed to take any avoiding action."
The BOI and Reviewing Officers had the same Met Forecasts and planning maps as the crew.