my guess, and it's only a guess, is that he held the knife normally.. and hooked the binding, and moved his hand upward (like doing a hammer curl)to try to break the bonding. Do it with enough force and have that blade come down on you, and bye bye finger. I'm sure he's an experienced guy, handy with blades, and has spent a good deal of time in the outdoors. (considering his record of success). He just didn't realize that when he was putting pressure to cut through that band, that he was also depressing the mechanism to unlock the blade. He's going to have a tough time winning in court though, especially since that he wasn't using the gut hook in the way it was intended to be used.
It is a good reminder for those of use who get out in the field a bunch that design matters. Only takes a split second to make a mistake like that in the field, and since we are out there doing things much more often than the average keyboard commando, odds are we might make an error once in awhile.
