One good thing that has come out of this thread for me are the contributions made by people I'd never come across before, like HENRA, CABBY and several others which, in my opinion, add to the discussion - thank you.
Obviously the old guard contributors continue to stay calm and educational to others from outside the aviation world.
IF.....one is to believe that eye witnessess heard popping/misfiring, then I would suggest there was an element of stall/surge going on. I've had both on two separate occasions whilst doing police ops. One was an air bleed breaking off the engine casing causing a surge with associated misfiring noises. The other was a compressor blade going for a walk at max chat and stalling the air flow temporarily before going into sulk mode all the way down to a forced landing on a cricket pitch where the game was in full swing!
On both occasions and for several very long seconds, I was confused by what the engine instruments were telling me. Ng/Nf were erratic, Nr was doing its best to stay governed but it was wandering! T4 was mad!
The point is, it took me about 20-30 seconds to isolate the causes each time (one was at night). Interestingly, I instinctively lowered the lever to arrest any decaying Nr that might have developed.
NOW - IF I had switched the wrong engine off duirng those early seconds, at night, whilst in the descent....the duff engine would have continued to protest, the Nr fluctuations would have increased because of only one (weak) engine remaining and my only choice them would have been to put the duff engine out of its misery. Doing that - then (in decent with lower than normal Nr) could easily have prejudiced the outcome for the worst.
Over the city, at night, getting very close to the roof tops, no engines - just PULL and hope???
[I still keep seeing posts from newbies assuming the crash was some kind of 'second bite' at landing. Believe me, we should all now be singing from the same hymn sheet - this cab hit hard...very very hard. Think 30G+.