Escape manoeuvres:
Blokes at the front = up
Blokes at the back = fall off the back
Bloke in the middle = pull up through boss' slipstream (you're going backwards anyway)
(Could be a blokess of course)
Line astern took a bit more bottle in that you had to hold your depth as you fell off the back and theoretically not take the fins off the boys behind you.
Seemed to work on the odd time we needed it in my day.
KMB01