I think vgamer 1981 made some good points. It is of course a factor, that you can nowadays download a copy of Schönbergs Harmonierlehre for free and know , how many culturally important composers have studied from it. On the other hand, I would consider some Jazz musicians culturally just as important, so one point for Spud as well!
But I really don't want to continue criticising here. I suppose the herd mentality of all the students here trying to defend it pushed me towards that.
But - just out of curiosity - have one question to you and I would love to get an honest answer on it:
I wrote about it earlier ... TC Jones offers his MIT (musical interval theory). As I said, I know one or two things more about it, as a friend of mine took his week-long seminar on the whole thing at The Hollywood Workshop in Vienna. From what I read and what he told me and the little things I know about EIS, it seems, he has adopted the same EIS principles, changed some things and now offers them has his own theory. Is that true?