Lol, yes, that is me in the video doing chin-ups. I was able to do that with the knife because I made it myself, and designed and built it to be very tough and durable. As several have stated, just because it's a hollow handle knife, doesn't mean that it's inherently weak.
As far as that other video, if you hit a knife with a metal hammer, expect it to break. It may not, but you're asking for trouble. Hitting a piece of hardened steel with anything other than wood, e.g. metal, is a very bad idea. In addition to possibly sending a shard of metal at you and risking injury, when you hit metal on metal, the vibrations are different, and exponentially increase your chances of failure of the knife.
That guy is doing that in the video for marketing purposes, and that's not evil, it's just marketing. But that is definitely not a recommended use of the knife, just as I don't recommend people do chin-ups with my knives.
Sam :thumbup: