I understand but my point was that I don't see any difference between how Dentokan would approach this exercise and Hakkoryu. I've not practised this particular exercise but I am sure, judging from the demo itself, that my instructors would teach the same principles. The aim of every dentokan aiki-jujutsu waza is to be able to perform without strength and proper use of bodyweight. The principles integrated into the waza are designed to achieve this - posture before technique as one sensei once put it.
I have no doubt that's the case. But, it's to the point of your OP to emphasize that I don't see a de-emphasis regarding aiki in Hakkoryu vs. Daito-ryu and aikido, but rather there are different flavors of these principles between Daito-ryu and its descendants, and in turn between Hakkoryu and its offshoots. Executing tachi waza from a starting point of being pinned to a wall by a ryote attack simply helps elucidate the flavor of a given interpretation.
I'd venture to say that there are notable differences today in those interpretations between Hakkoryu, Kokodo and the Dentokan. And, not only can the interpretations of the principles differ greatly from art to art, but also to a certain degree from teacher to teacher within an art, and student to student within a dojo. I feel that Hakkoryu, for its part in recent years, has reaffirmed its baseline interpretations and protocols by increasingly pointing out to the student body how the art today correlates to the original teachings of the shodai soke. So, while there are various flavors of kihon waza in terms of minutiae of form, the vocabulary regarding what the underlying principles mean is growing more cohesive within the art -- aided by the nidai soke's direct participation in these efforts in Japan and abroad.
In the spirit of the preceding advice in the thread, I'd encourage you to not adjudicate these things from the comfort of your computing device keyboard and the confines of your own dojo. There have been some remarkable discoveries and/or reaffirmations when people actively seek out a qualified other perspective (Devon, Richard and I, for example, have reported some of ours on AikiWeb).