What if it's ALL Chinese? And it probably is.
I would certainly agree. As a student of archaic religions in my younger days, what stood out for me was not the differences between the different manifestations around the world but the underlying similarities.
I think a lot of this stuff started farther back than anyone realizes or that could possibly be proven or disproved. But what happens as people move around the globe and distinct cultures emerge? Ellis used to talk about various obscure martial arts which served a very narrowly defined function within a given society. So an African tribe may take whacking each other with a long, flexible stick to a very high level or another might create an entire art around a movement that looks just like giving someone a noogie. Totally culturally specific.
So what happens to these skills when they go from China to Japan? They take on a form that is culturally specific. Pretty much anything that the Japanese samurai did involved an underlying foundation of weapons. The samurai was a walking weapons system. Additionally, he had to be bale to move wearing armor. So the form these principles took was based on the requirements of the users. What weapons did they carry, how did they carry them, armor, no armor, etc.
That's one of the reasons I have a hard time with the folks that look at Aikido and want it to be something it never was. It isn't, and never was in my opinion, an empty hand fighting art. The guys who developed the ancestor form(s) of Aikido were samurai. Their world revolved around weapons. That continued into Daito Ryu and then into Aikido. By the time that O-Sensei starts to change his ideas about what the fundamental purpose of training is, you start to see a gradual and accelerating divorce of the form of the art from any awareness of how the training exercise translated into applied technique.
It's not that you can't apply the principles of aiki in different forms... of course you can. But not in the form they exist in the art as we practice it. As any 14 year old twit on Bullshido will be happy to point out "No one attacks like that"! Absolutely correct, if by that they mean no one focusing on empty hand single combat in a sport context. But put the weapons back into the equation, as in the case of a member law enforcement who, like his samurai cousin, is a walking weapons system, and they get grabbed all the time. Many of the simplest Aikido forms translate directly in to weapons retention, weapons takeaways, etc.
So my point is that yes, I do believe that this stuff came from China. It may very well have come from India before that but I don't expect anyone to prove that either way. The Chinese manifested these principles in their martial arts as they fit their personal, social, political, technological and military context. The same thing happens to these skills when they travel to Japan. You can see forms that closely resemble the Chinese and you can see forms that are distinctly Japanese and would never be mistaken for anyone else's. Yet, these forms can share the underlying principle base.
I don't see any of this as controversial... more like a big, Duh! The question for us as modern practitioners of these arts is whether we are going to try to change them to make them fit our contemporary personal and societal requirements, which I would say we have already been doing, or whether we want to preserve a form, which may have intrinsic value in itself, but which might be somewhat divorced from practical applicability.
In the case of Aikido, if ones interest is in application in a contemporary self defense context, or especially if you want the art to apply against sport style martial arts (for some reason I still don't exactly understand), then you will have to change the form and the art will become something entirely different.
O-Sensei had volumes to say about how the form of our art manifested various principles of nature in an energetic sense. His "The movements of Aikido are the movements of the Universe" should not be taken lightly. I think that this understanding is crucial to keeping our Aikido on track as a personal practice that is in accord with what the Founder created the art for in the first place.
Dan points out that there is a huge amount to be understood about the spiritual implications of developing the internal principles of the art. I absolutely agree. Any time you place such focused attention on integrating the mind and the body, there are all sorts of things which happen on a spiritual level. That should be part of our Aikido; absolutely.
But I simply caution people against changing the outer form of the art before they have trained long enough to start to have a real feel for what prolonged execution of these forms over years and years can do for you. There isn't one single thing that Daito Ryu aiki has that won't serve to make your Aikido form better. But don't, in my opinion, do it because you want your Aikido to be more effective (although I am sure it will be) but rather because you want to understand connection on a far deeper level. That's the whole point of the art - connection. Getting to the place at which a feeling of connection is your default setting.