I know this is post-Aikido, but I recall reading somewhere that O-Sensei awarded Hikitsuchi Sensei a certificate in a bo-based system that he had created. I'm curious as to the influences behind it - maybe it was not even Daito Ryu based?
Here is an excerpt of an article published by Aikido Journal in which Ellis Amdur describes the Bo practice done in Shingu by Hikitsuchi Sensei according to Clint George, who practiced extensively in Shingu.
I would like to add that this is also the understanding that I was given by Clint George when he first returned from Japan.
I would also like to comment that my teacher, Motomichi Anno Sensei, stresses the influence of Nature on the bo form that he transmits and that he also stresses this is what O-Sensei communicated to him as the 'Nature of Aikido'. Anno Sensei says it is 'based on Nature'.
From Aikido Journal-
This scroll was entitled, “Bojutsu Masakatsu Agatsu” — True Victor is Self-Victory. Clint George, one of Hikitsuchi’s closest students, told me that the “Shingu bojutsu” had five levels:
Ikkyo — a fundamental solo form
Nikyo — a solo form that explored circular movement
Sankyo — a solo form that explored three dimensional, spherical movement
Yonkyo —Jiyuwaza — free, un-choreographed movement
Gokyo — Misogi no bo — a form that included techniques from the previous sets as well as those which had ritual, spiritual significance
According to Clint, Hikitsuchi disliked two person forms that were “long and dragged out.” Rather than kumibo kata, he would show waza applications derived from the forms. Hikitsuchi was much more concerned with what he called, kigata — “energy form” — the ability to spontaneously change as needed within one’s movements. Further, he emphasized inryoku — a “magnetic” power of attraction. This is a form of kiaijutsu, in which one sets up the opponent so that they conform to one’s will — the opponent is drawn into certain actions and positions that put him, inadvertently, at a disadvantage. Hikitsuchi’s bojutsu also focused on precision and clarity of technique, and he demanded an awareness of one’s openings, unified body movement and a feeling that one was in a real duel.