On coming back to this thread after some time, I find it getting ever more enmeshed in arcane issues. If anyone wants to overturn the verdict, they have to get away from technical nuances that the general public doesn't understand and get back to basics.
If you ask Bill Wratten why he decided what he did, he will give you a car driving analogy. He will say that if you drive up a motorway in thick fog doing 90mph, you are negligent because you are driving far too fast for the conditions. If a tyre bursts or a car slams on the brakes up ahead, you are done for. And you are done for, not because of the tyre or the car up ahead, but because you are driving dangerously fast for the weather conditions. Ergo, you are negligent.
And that is the nub of BW's argument in the Mull finding. From the reading of the evidence, the RAF hierarchy concluded that the Chinook was going far too fast for the prevailing met conditions. All the hypotheses about engines failing, computers going on the blink etc are seen as a red herring because if the crew had been flying prudently, they would have had time to cope.
As someone who was once responsible for coordinating BoI policy within MoD, I know all about not finding dead aircrew negligent unless there is no doubt. But BW and many others had no doubt that the Chinook pilots were flying far too fast, and therefore too unsafely, for the prevailing conditions.