I, too, am curious why the term was chosen.
I think I have a possible answer. I believe it has to do with Miyama-ryu Jujitsu, an American style created by Antonio Pereira. But I want to preface my suppositions by saying that this is tentative and in no way intended to slight practioners of Miyama-ryu or its founder. I have no comment about the effectiveness of its techniques because I have never seen it performed, and I have no hostility towards its practitioners; on the contrary I am envious of Pereira's opportunities to train with people such as Morihei Ueshiba and other very well known Japanese teachers of that generation.
From an official Miyama-ryu webpage, there is a brief mention of how Mr. Pereira, after his training in Japan, returned to New York and began a process of adapting what he learned to the specific needs and stressors of his urban community. Here is a quote:
Knowing that the Western life style and philosophy differs from the Eastern, he adapted the physical techniques and mind set of the Samurai Warrior to the culture of the dangerous streets of the modern, urban South Bronx. ...
...In 1964 he formalized the name of his eclectic method Miyama Ryu Jujutsu, which means School of the Three Mountains in English, or Tremont in French. This was the avenue on which the school was located. ...
In 1973 Pereira researched the classical ranking system of Japanese systems.
He decided to use the ranking structure and nomenclature of the Japanese martial arts, both classical and modern. He took the title of Shinan, which means originator.
(b/f, ital. mine)
It seems this was a conscious decision to avoid using the term "Soke" which he knew was incorrect for this application, and another Miyama-ryu webpage, which I am sorry to say I cannot find today, mentions that he offered the title "Soke" to his son as carrier of the tradition, but that his son refused. Leadership in Miyama-ryu was disseminated among three of Mr. Pereira's students, none of whom use the word "Shinan" for themselves, but to refer only to their teacher.
The individual in question, Mr. Sharpe, has studied Miyama-ryu in the past and apparantly taken this word to refer to himself. A discussion of this individual, as well as a fine example of web-cross-self-referencing in the most po-mo of ways, is currently here, in "Baffling Budo" forum. I will leave it to my betters and the more experienced to further examine Mr. Sharpe's claims, rhetoric and appropriation of the title "Shinan". I will say that one of the leaders of Miyama-ryu, D'arcy Rahming, is a member of e-budo and that he is perhaps the best equipped to further talk about Mr. Pereira's use and choice of the term, as well as Mr. Sharpe, should he choose to.
I know most posters here are familiar with Miyama-ryu and Japanese language/culture to a greater degree than I; most likely others have drawn similar conclusions. Yet I thought perhaps a bit of "filling in the blanks" as I see them may be useful for further discussion. It seems from my point of view that Mr. Pereira's use of the term "Shinan" is a separate issue and one without negligence, yet perhaps was the inspiration for Mr. Sharpe's use of it. But then again, I am speaking from a novice point of view.
Respectfully,
J. Nicolaysen
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"I value the opinion much more of a grand master then I do some English professor, anyways." Well really, who wouldn't?
We're all of us just bozos on the budo bus and there's no point in looking to us for answers regarding all the deep and important issues.--M. Skoss.