Generally a very good video. He's talking about the things we've talked about here for years, thin comfortable handles with some flex to them. But he makes these ideas more accessible to a wider audience. And videos are often more instructive than text.
I like many of his videos. I appreciate that he doesn't endlessly self-bloviate like another popular youtuber.
A lot of what he is doing can be done much quicker with a larger wood rasp or new sharp farriers rasp.
His wooden maul is well made. I like how the transition from head to handle (see 17:45) is a gradual taper that doesn't create a weak spot.
Adding 'hook' for the little finger at the bottom of the swell is something I've preached here for years. But I don't want the hook too close to the end of the haft. If you do that, especially with an clipped fawnsfoot, you end up with the end of the swell in your palm where it can raise a hot spot. Better if the top of the swell continues all the way through your hand. And he's right that wide swells are better.