Well I was thinking more in my own experience of playing the flute. I haven't played for almost 20 years, and learning a new song is no longer possible, as I can't even remember the notes consciously. However, give me a music piece I've played when I was younger, and I don't think about it, it just comes out. My fingers somehow 'remember'
(I am aware that Si is supposed to be my inferior function, so I'm sure it's not as well developped, but it still makes me wonder)
Same for my photographic memory. When I take a test (and I've really made a point of studying), I literally 'see' the book or notes in my head and I turn the pages in my head till I get to the section I need, and then all I have to do is copy it down. So I'm wondering if that too is Si..