For such rare instances as if your hand is disabled, either in a fight, or before hand such as you are in a cast from a broken hard/wrist/etc. One of them things you will never use but doesnt hurt to know. We were able to get my brother to work my Mossberg 500 when he was in a cast from hand to elbow so he could skeet shoot with us. He did alright. He couldnt flex his hand to grip the pump so we had to work around it.
Elaborate in this instance is left much to opinion I'd say. I can do it on my belt if I really need to, or fumble around trying to hold the grip in the back of my knee or whatever. This is just what at this moment works best for me and my auto IMO. I switch between a shooting grip and this one in an acceptable amount of time, with adequate retention of my weapon, and without moving the muzzle so far away from my target.
And THR = thehighroad.org...another very good site, similar to this one