I feel like there is very little martial about this practice in terms of how a person might practice 1st control for getting an arm bar in a fight. Anyone watching would almost for sure wonder what the heck we were doing, and what the purpose was.
The purpose for me is what I feel in my body and my partner's body, the sense of connection it builds in and between both bodies, the improvement of balance from odd positions, etc.
In the Ikkajo exercise you describe, do you think there might be martial training value in gradually
increasing the speed of movement (and force) provided by your training partner while you test your sense of internal connection? In the context of yiquan, I got the impression from the two teachers I worked with that the solo practices work in tandem with their shili (strength testing) and then push-hands to provide a training gradient with increasing force and speed where the practitioner learns to maintain internal connection and balance under progressively more difficult circumstances. One teacher mentioned something along the lines of training the body to the point of responding almost "automatically".
There are tales of masters in taijiquan and xingyiquan relating to spontaneous, seemingly unconscious demonstrations of internal strength skill. In one such story, Yang Chengfu (Yangshi taijiquan) was walking across a bridge in Shanghai ca. 1930 when a rickshaw runner accidentally ran into him. Rickshaw and runner bounced off and went sprawling, while YCF continued on walking and maintaining his conversation. Chengfu's relative size (6', 300 lbs.) may have something to do with the outcome of this encounter, but the story is told in Yang taiji as an indication of YCF's level of internal skill. The point of this kind of story is less the precise factualness
and more the type of skill illustrated/underscored by the story.
It's also interesting that some stories of Chinese IMA masters in their prime suggest that they maintain a narrower scope of practice in terms of numbers of different exercises and forms, and a focus on cultivating basic attributes continuously, rather than putting lots of times into lots of different forms (though they maintain a knowledge of those forms).
To use Yang Chengfu as an example again, apparently it was rare to see him actually do any part of the solo form sequence(s) that were taught publicly and earned him his bread and butter. YCF would practice four or five individual postures from the solo form and the transitions into and from them. He would also do quite a bit of tuishou in training. In his younger years, basic training (aside from the long solo sequences) would involve zhan zhuang, a neigong set coordinating movement, breathing and fajin (see http://youtube.com/watch?v=P0DLuiBBkNs)
, and solo thrusts and circles with a long pole or spear (see, for example, http://www.youtube.com/watch?v=RsWUe3PfY_o&eurl=
In Chen taijiquan, Chen Fake, the pre-eminent teacher of the style in the twentieth century, would move his arms in small chansi patterns while sitting in conversation, in a sense never stopping practice of basic attributes, according to his last surviving disciple, Feng Zhiqiang. Feng himself, despite continually creating new solo form sequences, spends the vast majority of his personal practice time engaged with the chansi, hunyuan neigong and standing exercises rather than elaborate solo forms.
I don't know whether the basic practices of yiquan or taijiquan are cultivating the same precise internal connections and skills that Ueshiba shows. But the general idea of high-level martial practitioners refining their practice to the essence by focusing on basics seems similar. What basic practices Ueshiba probably focused on is of course discussed by Ellis Amdur and others in some depth.
What we've got now is an interested group of aikidoka and practitioners of other arts discussing, demonstrating, sharing and cross-training on internal basics. With skill developed over time through persevering, focused effort (the definition of gongfu), people will--already are, considering the efforts of Aunkai practitioners--improve, and test, and share. It will only be a small percentage who realize and can readily demonstrate real breakthroughs, perhaps, but these are very interesting times and discussions to be a part of.