I think the worry is that in a monohull you have all this sail up and you can't stop the boat or drop sail quickly enough. In the story, the boat was knocked down and stayed down... but she was still trucking...all be it on it's side. The remaining crew could not recover their second crew member and stop the boat at the same time.
My point was to put some numbers to idea that you could be tethered to a cat at speed.
