Ah, true. Forgot that part of the style. Up to GM supposed. If this is the case then Mibu clan has damn good swordman and as kind of rising prodigy in taijutsu (born genius and also adept) Tashi is the student who has been taught the style exclusively. Gives him bit special status even before he starts manifest his True Red Eyes (where things indeed go serious level as having True Red Eyes is kind once per generation deal).