Fascinating stuff.
And interesting comments about the A321 as well; seems like they might have similar issues getting out of the sky too - we were effectively vectored to 'undertake' one that was having some issues making the clearances into BRS the other week.
The f/o reckoned he could see 'uncharitable' hand gestures (am fairly certain he was joking) from the other flightdeck a couple of thousand feet above.