Bearing in mind that there is a lot of hokeyness involved in many of the demo's and the Uke's tend to be dive-bunnies, I'd have to say that Takeo Nikishido at least exhibits enough to tell me that he indeed has a very good grasp on how to use ki/kokyu-skills to do "aiki". Not that I'm judging from on high... I just mean that there is enough information via the video to make me personally feel sure without being able to feel him personally, etc., to make the call.
To me it’s like watching paint dry. As a display? I'll judge it and willingly back it up physically. This guy’s not that good. Of course being a Japanese art the Uke's are a mess and once again exhibiting pre-conditioned responses –this time ala Daito ryu ukemi. Under resistive stress and a more live environment, you would see a drastically different video. Sadly the art will forever be limited by those who train this way. His uke’s are holding him back from further progress. You can see it in his body. Their attacks are one-side weighted and using muscle and then receiving his aiki without changing it. If you could get him to train with better, non cooperative people-who themselves know aiki and how to use it in active resistance- then through the realties of "aiki-meeting aiki" he would, by necessity, have to soften his approach to his art. In other words, over time His uke’s would- through active changing resistance- help him to learn to use his body with a more fluid connection to absorb, emanate, be changing and playing with their energy and thereby cover a broader range of attacks. I've no issue with his intent causing aiki age rise and aiki sage through his spine, as well as his connection with their center on contact. It's just one directional and limited.
The Japanese model in what the uke's do with that energy is a false premise and exhibits and contributes to an artifice in both themselves and the art in general. There are several ways I can think of to quite literally take him apart where he stands.
I've no patience for that Japanese pre-conditioned reaction crap and I yell at people for doing it all the time. No one I have trained, will ever respond to that level of input in that “trained monkey” fashion. They will change force instantly and keep coming. They train anti-aiki to be a natural occurring state of conditioned movement in their body. That said...don’t assume everyone trains like this guy.
Using the above information, I'd back-interpolate differently that Dan Harden does but arrive at the same conclusion... the bulk of Ueshiba's skills in "aiki" almost certainly derived from Takeda, although I'd hesitate a bit before I'd say that all the ki-training methods came from Takeda. And the ki-training methods are important; there are a number of methods to training these skills and Ueshiba appears to use the more classically "soft" approach than I personally see in most of the DR experts. But that's a personal opinion based on my own background.
I've always recognized you were interpolating that aspect-what was in DR that transferred to Aikido...from a distance. While I respect the body of knowledge you bring to the table, I never discussed that specific aspect “from a distance” I had a different view having trained in both arts for years. I had detailed reasons for drawing my "conclusions" one of which is the soft approach was in the body method of Daito ryu already. Aiki in/yo ho (breath power) and fure aiki is extremely soft with great potential for “listening” and changing energy. I see a natural progression-not an improvement-from Ueshiba’s DR to his free flow aiki…do. Strip away his spiritual beliefs and his thoughts of being one with the gods, even with his modifications in solo training that we’ve all done, and what remains are the body skills of DR shining through.