I have just watched Sensei Lemus (of Oneminutebunkai fame on youtube) perform Sokon "Bushi" Matsumura's version of Seisan.... and I noticed it's remarkable resemblance to Hangestsu.
I am aware that Seisan was the original source of Hangestsu but most other version's I have seen do not so closely match Hangestsu or Wado's Seisan form (both of which clearly have a common ancestor). Is it possible that Matsumura's version was the original scource for Hangestsu, especially given that Matsamura was Itosu's teacher? Ultimately I am interested in the comparison from a bunkai interpretation point of view ... and just plain historical curiosity...
I am hoping some more knowledgable members of the forum, might be able to enlighten me..