I think I originally thought you meant that the very secret of aiki was itself transmitted through the ages. Now it simply seems like you are saying, Aiki comes from Asia.
I'm not going to deny that.
With regard to the quote from Mr. Threadgill, first of all, thanks for digging that up, and I apologize for making you do that legwork. TSYR is one of the koryu schools to have been confirmed as having some solo work as part of the curriculum. Though you would have to be admitted into that system to really know how central it is to the training.
Yagyu Shingan ryu has some as well, I believe it is taught in both the main lines to beginners, and I hope to have the opportunity to look into it further at some point in the future, will let you know.
Toby Threadgill holds a bunch of different densho in trust of the TSYR and should be taken as a reliable source of information on the history of classical Japanese arts even outside of his own. But to put it simpy, I keep looking around for these crucial solo training systems and I keep coming up with nothing. I've spoken to people who practice all manner of different koryu and scant few of them have been taught solo training.
Most of the koryu schools that exist today were once comprehensive systems, with a grappling component. So you would expect that just about any existing koryu would have some traces of solo training in their curriculum if it was so important to developing martial skill. Kashima Shinden Jikishinkage ryu (really important to the development and dissemination of Daito ryu IMO) has a suburi practice, as well as breathing and walking practice that are distinctly internal, that's about it. And that's the school with the crystal-clear link to China, as the key soke (fourth lineal headmaster?) spent several years in China after Tokugawa took power.
(FWIW Here, on Chris Li's blog,
is a diagram that depicts the Jikishinkage ryu suburi, practiced in the Sagawa dojo.)
Well, another thing to look into would be Judo. How prevalent was solo training at the Kodokan while Kano was around? There were dozens of koryu systems known for their strong jujutsu that were absorbed by the Kodokan. Kano was very interested in preserving them. I think if solo training methods were important to these schools, that would have translated into Judo, at least during the early days. I will look into it and let you know.
So how about it guys? Can we start talking about "aiki" as being essentially a "brand" of subtle jujutsu, that has loose cognates in many different systems? And note that in these other systems, paired kata are considered sufficient for developing these skills? Such that, if you choose to purse a solo training regimen, that may be a tremendous benefit to your own practice, but it is clearly not neccessary or integral to development of skill at creating aiki?
Personally, I think we have to accept that "aiki" as used in the general sense, and even within the Daito-ryu-sphere, is not strictly wedded to IP (e.g. as defined by Katsuyuki Kondo, e.g. in the DVD What is Aiki
, in which it is described in a tactical vs. body skill sense). In addition, Sagawa went on at length about the inferiority of certain "aiki", relative to other "aiki" (namely Sokaku Takeda's and his own mousetraps).
That said, for the purposes of addressing the theme of this thread, Ueshiba's aiki (like Sagawa's, Tohei's, Tada's and others' known to have uncommonly powerful aiki) was IP based and developed via solo training, per the Aikikai Hombu as cited by Peter Goldsbury. Most aikido doesn't have such aiki today -- ergo, they can be and typically are today, demonstrated as mutually exclusive things.
Cliff, the judo thing is interesting. I'd be very interested to hear about what you find out. Over here, I'm introducing this discussion to senior members of the judo club where my family trains. This dojo, the Shobukan, was visited and named by Jigoro Kano, and is reportedly the oldest extant judo dojo in the west (by virtue of having been a U.S. territory, and now state, if not by geography). So, people at this particular school have an appreciation for the historical aspects of judo, in addition to a mission to take as much hardware as possible at the next state tournament on the schedule. One sempai stated to me that he believes at least one of the judo kata inherited from koryu is designed as paired IP testing, in its ura interpretation. If there's anything more salient that comes out of these discussions, I'll report back as well.