dvcochran
Grandmaster
Ivan, I have used the ridge hand to break six boards horizontal. It is all about the structure of the hand and what you strike with. I have seen a lot of people try it will a loose hand hitting most or all below the index knuckle. Very painful. And pretty stupid/lack of teaching and/or practice.I've seen this in Taekwondo and it's called a ridge hand, though it doesn't seem to be as circular. The reason it's not used is due to the immense pain you feel when using this full force. We trained this on kick shields and a hot searing pain always shoots up your thumb, because it's almost impossible not to make contact with the first thumb join no matter how much you tuck it in
From what I see, the hits are slow, and use circular swinging motions to generate power which seems inefficient as personally, I'd find it easier to generate momentum by kicking off the ground; the only advantage I can see is that it's a very unorthodox motion, but doing this in the modern era of martial arts fighting and combat sports is begging for your opponent to weave underneath and shatter your liver.
Nevertheless, it looks like northern kung fu, and that is powerful stuff. I recognise this movement from here:you can see the punches around 0:25