In reply to Colin Moody:
the winchman hanging over a very small boat, in a lake has little choice, but to single or double strop him up. It would be near impossible(there are extreme ways, but it's far from easy and is very time consuming) for a sole winchman to lift an adult into a stretcher, all whilst both are hanging from a wire, with down draft, even in perfect weather conditions in the middle of a lake.
So do you wait longer for ground forces or do you push on? It's risk management, in a potentially high risk environment, high risk injuries etc.. so statistically it simply won't work 100% of the time, but 99+% it does and hundreds owe their lives to it. Whilst you had to trawl back a bit to find these rare events, you probably missed the many 100's, perhaps 1000s, of winch based rescues that worked perfectly.
Post edited at 07:28