I'm not going to go into this here, but in Daito Ryu there are explicit relationships between Japanese Buddhist and Shinto practices/philosophy and the techniques/worldview of the art itself.
These relationships are also prevalent in in traditional forms of Japanese flower arrangement and music. These are just two that I am in some way familiar with. In fact, pretty much any traditional form of Japanese art should have these philosophical links IMO.
My point is that Daito Ryu is not "merely" a vehicle for "Internal Strength" training. It is an art with its own traditions, history and "spiritual" (For want of a better word) worldview.
A great post, by the way!
thank you, I did not know that was the case for DR.
I should have been clearer: What I think will not work is isolating out "aiki" as a physical method from a complete culturally specific package (Morihei Ueshiba's practice) and then reintroducing it somewhere else to make spiritual improvements.