I realize that lineage, especially ninjutsu lineage, seems to be an important topic these days. Seems to take precedence over the actual system itself. I don't understand this at all. Bottom line, if the system works, it works, if it doesn't, it doesn't. Can someone tell me the lineage of Boxing?
To answer your question, there is no lineage to Bansenshukai since it is a system I have created. I can tell you what has influenced the system though.
First and foremost, the actual Bansenshukai text, which a historically verifiable volume of works written in 1676 containing various strategies, techniques, principles, and tactics of Iga and Koga ninja. This is combined with other such texts such as the Shoninki and Ninpiden. These are the major influences for the skills set we implore.
As far as the taijutsu, it is influenced by Takamatsu-den kihon happo in many aspects. However, the taijutsu has been updated to meet modern day attacks. For example, we are heavily influenced by boxing in our striking methods and rarely use a forward lunge punch. We also have been heavily influenced by AJJ, as most x-kans don't even scratch the surface of ground fighting.
We have tried to make the best system we can which not only looks at all areas of conflict; striking, throwing, choking, joint-locks and breaks, ground fighting, etc. but we also require actual ninjutsu such as shinobi buki, hensojutsu, intonjutsu, etc. in each and every one of our kyu levels.
Our training also aims for a balanced regiment. We train slow and smooth, move into tai sabaki (free response) and randori.
Hope this answers your question. No lineage, we don't even pretend to be "traditional" ninjutsu, however, our entire curriculum is based on modern day, tried and true, principles and training methods.