Hi there,
I was thinking that Shinto/Shinshinto blades couldn't receive Juyo by definition, but then i came across this blade,
http://www.sanmei.com/contents/media/O454_S828_PUP_E.html
which is dated to 1681, Shinto.
Wiki wrote:
Would this blade be one of the exceptions?
And would it even be possible, maybe in a hundred years, a Shinshinto piece would slip through?