Dan Harden wrote:
The movement, and more importantly the body method behind it is expressed in Shiodas technique ...ala Daito ryu. In fact the rebounding is from an establishment of a current- the same as Mike's "ground path" (can't find a TM font) description and using that path as an internal spring. It is a training tool in DR. Which Ark knows about as well.
Whether it is Hiriki or chest matters not. So is the knee technique he uses. Its DR. and.......its in Tai chi.Gee what a surprise.
It's in most Chinese martial arts. It's the basis for "Swallow and Spit". I could point out 3 or 4 ways to really boost that power... i.e., there are variations of that one technique. Some of the variations are very powerful, some wind, etc., etc., etc.... that's where the names for the different jins come in. Variations of the core jin technique.
The core jin force that O-Sensei used is also the correct force that should be used in a "Kokyu Throw". As a matter of fact, this utilization of jin should be in ALL Aikido throws, but let's not get ahead of ourselves.
The force O-Sensei carries through to his chest from the ground is exactly the same type of force/jin that Tohei uses in his "ki tests". A jin/kokyu-force deriving its support from the solidity of the ground (while the body simply channels that solidity) is what I tend to call a groundpath. A jin/kokyu-force that derives its power from the weight of the body (the body channels the center of weight over to where it's need... more 'mind-body' skills) is the other type of force and sometimes it is complementary (a "push" can be "out of the ground" and "down" at the same time, for instance).
The trick is often in the reflexes and in the methods that power is stored along the path. O-Sensei used a mild bounce into the floor, coupled with his forward, ground-driven body movement in his response to the chest attack (the one he signalled for, so he had plenty of time to set things up, BTW).
In other words, I'm saying that in that simple demo that Ueshiba did, you can see the core force of all of Aikido, Taiji, Xingyi, Bagua, Sword arts, Calligraphy, Ju-Jitsu, Daito Ryu, Ushiro's karate, and so on. It's a good thought starter for someone who thought all of this was a complex issue. Look at that video and learn.... all things are the same thing.