On Sun, 16 Jun 2013 14:15:43 +0100, Walt Connelly
wrote:

[snip]

One might think that an engineer could design a system which would
overcome the force on the tow hook which exceed the pilot's ability to
pull the release. I've heard of a condition like this happening when
the glider pilot "thought" he had released and in fact had not. Never
sure how things like that happen.

There was a tow-pilot fatality at my former gliderport years ago, in
which the towpilot apparently couldn't reach the release handle while
he was holding full back stick to avoid being nosed into the ground.