Thanks Courtney. To be clear though, once you discount a bunch of causes you are left with just a few to decide between - I do think that the video provides enough to make some very clear deductions. I will not post the conclusions that I arrive at because I am conscious that they are then open to misquoting, or could be used maliciously - but over a beer among fellow-professional I think we could arrive at a 'most-likely' explanation already, notwithstanding some inevitable (but only contributory) unknowns. And we must, of course, consider all options, and not shy away from some just because we feel that it is an insult to us or our colleagues. We have similar experience btw.
Bottom line is that it is bloody awful. Per ardua.