Ollie Onion
Yes there will be mitigating factors such as the 'training' taking place, but the fact that there were FOUR pilots on the flightdeck and NOT ONE of then seemed to notice the speed deteriorate to 30 - 50 kts below approach speed (according to ADSB data) is quite frankly gross negligence.
Now, I could very well be wrong here, but having read this whole thread, I do not recall it ever being categorcially stated that all 4 flight crew were on the flight deck. On the aircraft - yes ("2 crews operating in shifts" [NTSB]), but not necessarily in the jump seats.
That doesn't detract from the "gross negligence" (should the presumed situation turn out to be the ACTUAL situation), not least that the PF (albeit new on type) has been flying 747s for a number of years, including into SFO and had a training captain as PNF (as it seems was the case).
Regarding one of the posts from a few pages back that questioned why the approach lights hadn't been "taken out" by the "tail in the water", from the debris track, it would seem the final approach was somewhat right of the centreline, which presumably also explains why the farthest left PAPI support is intact whilst the others are gone.