Thanks for the reply.
What you outlined there sounds about right. I admit I only read it once, so maybe I missed something, but so far, I think I can agree with what you are talking about.
How is that different then something athletes do? I know, this is kind of vague, but I'm trying to get at why Internal might be different then external.
We both recognize that both "IP" and "EP" uses relaxation. And both use "ground-path" or the ability to direct something from an appendage/body part to the ground. And they both use good structure, they ability to hold the frame in a relaxed state. So, how is "IP" doing this differently or better then someone trained in an external method?
Sure, I've trained with or attended seminars with people who range from BJJ browns/purples, state power lifting record holders, army rangers, Kyokushin champs, guys with MMA records etc, none of whom could replicate the sensations you get when you touch someone who has IS. If they moved me dramatically, it was the result of a windup of power, momentum, rotation, physically dropping etc. Thats basically the point of Sigman's teacher test. If you push on the shoulder and you get moved without the teacher moving at all, then they have something worth studying.
None of the people I listed above, were able to do that, despite pretty good athletic backgrounds. There are guys who can generate considerable power, externally, but it has a different quality to the result. Mainly that it lacks the unbalancing sensation achieved with no windup.
Now we can see where some of this stuff used to be in other arts. For example in the judo kata, itsutsu no kata, you see some pretty "wacky" stuff.
. Quite honestly it makes no sense, in modern judo, there's no waza, per say, no bunkai, and both gentlemen move in a very strange way. One guy "falls" backwards in a way that suggests he should be unbalanced backwards, but is obviously moving in a way that he is falling backwards because the choreography demands it. In some demontrations of this kata, you will see the uke standing on his toes as he goes backwards. To me this is an indication that IS was present at one point in judo, or its precusor arts, because you would have to utilize it to knock someone back in such a manner with no wind up, such that they can not regain their balance. Plus popping up on one's toes is another indicator. I could go into a bunch of other stuff in that video in terms of what it appears they should be demonstrating, but I would repeating stuff we all went over a few years back. I will note that various hachidan level judoka say, its achieved by moving the thumb and forefinger to knock the guy backwards, but in videos with that level of judoka, it still looks like this video.
Now I don't want to say that the only indicator of there being IS, is this unbalancing phenomena, but to me it appears to be a key constituent component of aiki.
On a side note, Dan John's videos are pretty sweet. What he is teaching isn't IS, but a component of what is needed to make it work, namely how to access the kua. You can have a look at one here.