Members: Failure of the Cats Paw Knot

The Cats Paw knot is mainly used by anglers but is also occasionally used by riggers to shorten and attach a sling to a hook.  The question raised here is whether this knot could be useful for rock climbers.  It would appear to have the benefits of both shortening the sling and providing some shock absorbing capacity as the knot tightens during a fall.  The tests detailed below attempt to assess the appropriateness of the Cats Paw knot for use in rock climbing activities.