I do remember
knowing about the program in the 90's, even had a try at its chord entering interface in the music store... where I was to buy one of them keyboards which could do that instantly (plus BBox not on the Mac yet at that point), so I never really paid any more attention to it at the time.
But then two things happened in a short span - it came for my precious Mac platform, and so did the Realtracks - and the rest is... well, now you're stuck with me

p.s. I have to wonder, about those tasty floppies - red or white to go with, what you reckon??