Interesting to take my quote... In the larger context I was arguing that since aikido has morphed in so many directions then what is important as core concepts/ principles/ methods/ whatever vary tremendously. Hence arguing about this stuff at that level is kinda silly.
But... My personal opinion is another thing entirely. And I would argue that very few ever got to a high level in what *I* (see, my POV, my priorities, my background) consider fundamental. I sure as heck haven't. And I see some of that as a lack of transmission due to a variety of factors.
The major one, I think, is that those folk who did "grok" some of this stuff "groked" it in a way that simply couldn't be transmitted to someone who didn't have the same experiences. Their understanding of how they were able to do these things wasn't well formed due to a lack of a conceptual framework which makes it a difficult proposition at best to teach. I think many of those who are very, very good in fact don't really understand how they got there. But they did. And they tell you to relax, to not muscle, to just move their center like they do. What they don't see is that they spent years developing that ability through some mix of methods and now that they can do it they can't explain how they do it. They just relax. But if we "just relax" it doesn't really help. Why? If we adopt a point of view that some degree of physical development is necessary to do these things then you have a person trying to explain a feeling to someone lacking the physicality to feel it themselves. Honestly I think some who have some degree of these skills do feel (what they take to be) the "ki flowing", do feel that connection, they just don't have a mechanism by which to explain it that goes beyond semi-mystical concepts. Hence the conundrum we find ourselves in.
"Aiki requires an enormous amount of solo training. Only amateurs think that techniques are enough. They understand nothing." Sagawa
THe information is NOT in the techniques.
Over the years this has been my experience as well. The training methodology most of us have used over the years is learning to do techniques along with various exercises with the hope that we get that elusive glimpse of aiki as we go. So the footwork, positioning, postures, etc. that we work on aren't so much to learn to the technique well, but to hopefully "stack the deck" so we can start to build up a structure, balance, approach, then develop something that allows this magical aiki thing to start to make an appearance. So to me it is like tossing down the little footstep markers on the floor to teach someone a dance. It ain't really about stepping in each spot. It is about guiding someone into being able to finally do it with grace, elegance, etc. and hopefully at some point -- they simply dance. Without the footsteps. I.e., the techniques themselves were simply a heuristic device to get at something deeper, more fundamental.
So while one can start to "grok" some aspects, it seems to me to a be a poor transmission methodology since most students simply emulate the movement, the dance steps, without ever grasping the underlying "power" that drives it. I think some of the movement to IS/IP is trying to focus on that power which can then be fed back in to the techniques to see how they can be done fundamentally differently (all while often looking almost exactly the same).
Cart before the horse...
All that said I've met and trained with people in Aikido who are marvelous technical artists. Their movement, strength, balance, etc. is just fantastic. But in my personal classification what I see is really good, solid jujutsu. Good empty hand waza with good physical presence. I marvel at those people, but I'm not so sure that good jujutsu is the same as the aiki I was looking for in training in aiki-do. But here I see the focus on technique. Good solid technique that would probably leave me in a crumpled mass on the mat. That's good stuff. Just not what fits in to *my* conception of what I want *my* aikido to be.
Anyway, I felt obligated to post since it was my quote that started this thing. I won't get in to the whole "was it handed down" argument because it is a question of degrees. I think Tohei did a marvelous job with his focus and he gave us a lot of tools for learning. But it's okay to look for more tools to investigate the same thing.
Or if it isn't your bag, there are other ways to approach aikido that I think are perfectly valid, like the "technician" approach I outlined above. I respect that greatly.
So... that's my framework for understanding... FWIW.