Just completed comparing Mabuni's 1933 text on Sanchin to the one discussed previously on the Shito Ryu site.
Very much the same kata, the only real difference is there is a second mawashi-uke/tora-guchi in the clip.
But Sanchin was never really a defined, only 'x' number of moves kata. It always had the ability to use multiple repetitions of techniques in practice, sometimes moving completely down the floor for one section.
The goal wasn't to do sanchin in proscribed movement, it was to study Sanchin.
So I would rate the Shito-ryu sanchin clip almost a direct transmission, or a direct transmission of the form.
bushi no te isshinryu
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