Bob: Thank you for your very complete and thoughtful response, and thank you for allowing me to draw you out. I understand your reluctance to get involved in endless internet discussions, but what can I say--I enjoy them, and I enjoy the occasional theological or political online slugfest too.
I also apologize for giving you the impression I was riled up about the content of your first post. In trying to figure out the relationship between aikido, daito-ryu and internal arts, however defined and between Ueshiba, Takeda, and Takeda's teachers, we are all trying to put flesh on dry bones--and the bones are very dry. We'll likely never know the truth for sure, so why get all bothered about differing opinions?
So let me respond with my own view in juxtaposition to yours, though I expect little of this is new to you.
As I understand it, the argument goes like this: Takeda learned elements of internal arts from sources that are no longer clear to us. He taught them to his students, including Ueshiba and a few others. Ueshiba took these skills and the jutsu that framed them in his own direction, eventually creating a new art. Especially post-war, as the organization teaching this art grew rapidly, the internal skills were lost and the organization focused on the external form.
Dan H enters the picture as someone who learned the skills through a daito-ryu line in which they were preserved. He bounced around the interwebs making noise until the respected Mr. Ellis told him to put up or shut up. He did, started working with people publicly, and a bunch of senior aikidoka recognized what he was doing as something missing from their own art. Howard Popkin has a similar (but independent) background and shows similar skills, indicating that this isn't just a Dan thing.
Independently, Dan also started working with senior Chinese martial artists and they also recognized what he does as variants of or important elements of their arts.
So as I see it, no one is trying to jam Chinese martial arts into a Japanese art where they don't fit. Instead, they're trying to fit skills that were naturally part of the art back into it. That the fit is natural is confirmed in several ways: by the historical connection; by O-Sensei's use of metaphors and concepts that match those found in Chinese martial arts; by the reaction of senior aikido practitioners, including a few who took ukemi from O-Sensei; and by the way that the concepts Dan teaches helps decode what senior aikido practitioners are doing.
Operating from that premise, arguments about what exactly "internal power" is or even what "aiki" is are, for me, beside the point. I would expect that the Chinese arts would have a richer vocabulary and set of concepts than either daito-ryu or aikido. We're getting them filtered through one man, after all, if they even came from China at all. The historical connection to Takeda and Ueshiba is interesting and relevant--the rest of it is speculation.
And yet, the training we're doing now with Bill Gleason and Dan seems to have some relationship to the Chinese internal arts. We are explicitly taught to use "relaxation in place of timing" rather than depending on speed, perception in place of strength, whole body movement in a way that's different from the usual aikido use of the term, lots of visualization, and we try to avoid double weighting (however unsuccessful we may be). It's intriguing to think there may be a historical connection, though I don't think we'll ever know for sure what it was.
The connection between Ueshiba's skills and weapons training is a fascinating subject. I've heard Gleason Sensei say that he feels his sword practice was most helpful at giving him a head start on the skills Dan is teaching. I myself am finding all kinds of connections, though I'm not an independent voice here--both my teachers are showing the connections explicitly.
I'd love to look more closely at how spear work fits in. Anybody know a good school in the greater new england area?
Hugh, as someone wrote elswhere in this thread, it is not the spear, but how the body moves while holding the spear, or perhaps more specifically how the body is forced to move while holding the spear. It is long, and unwieldy, and requires a certain body organization which, to a thoughtful practitioner, can make quite a difference on empty hand techniques. (As an aside which will no doubt draw some ire, I don't think the jo is really adequate to the task on the development side, but certainly is once one knows what one is doing.)
Anyway, I would posit that two essential elements of discovering the internal were having to move in armor and using long heavy weapons such as the spear, staff, or battle sword. I think this is very obvious in one very prototypical sword style (katori) and one very prototypical taiji style (Chen - which I don't study by the way). (Of course there are other arts as well.) There are certainly ingredients necessary, since most cultures developed armor, but budo is, well, budo.
But to your specific query, I know of nothing directly in your area. I tentatively recommend one or both of the following: Look up the Gin Soon tai chi group in Boston. (I was for a while the student of one of Paul Chen's father's students who now teaches in Providence. There are some very, very, senior people to be found there, and some skills of a very, very high order. But like most things Chinese, very little is in the front window.) They certainly teach spear on the back end of things as I remember, and along the way one will obtain some first rate internal skills.
The other thing I recommend is to seek out the katori shinto ryu which also teaches spear on the back end. I may be wrong but I believe that Dan does, or did, study with Larry Bierry (sp?) in New York. I assume there is a work group somewhere local to you.
Thank you again for you reply. Sorry I could not be more helpful. Although I grew up in Providence, I've been down this way for nearly 40 years and am not sure what is around. Both the options I gave you would give you (eventually) what you want, but again, not right away.