Eric Pearson Sensei of "The Nameless Dojo" in Austin, Texas teaches Daito Ryu aikijujutsu, Tomiki Ryu aikido and Matl Ryu judo in the muteshokai style.

He said something recently that is an expression of commonality; and which made an impression on me. I think this would be helpful in explaining where Hirakawa Ryu comes from.

A basic explanation for Hirakawa Ryu waza (techniques) is:

.

(ken muto tou itsu "The same with or without a blade")

Daito Ryu emphasizes making a connection between combatants; Hirakawa Ryu emphasizes creating a flow between combatants. As time passes I am more convinced that these are the same...

Anyway, Pearson Sensei on knife work:

"I was hanging out at a Chinese restaurant with George Ledyard and Howard Popkin. The conversation turned to knife work. I mentioned that a lot of my practice is knife work.

George asked me a strange question..."what type of knife work?" My thought..."what does he mean? Pointy end in bad guy!"

Thinking about it, universally aikido people suck at knives. My 1st Daito Ryu teacher, Ikuo Ota, taught all aiki technique is based on the blade. I have spent almost a decade now focused on working aiki-tanto. I have been trying to patch up the sucky knife work of the rest of the aiki world.