Wow, this sounds amazing and mind-boggling and all kinds of enjoyable to think about. I know oh-so-little about Japanese history and culture, but I did know Zen culture and the like was a product of what I would consider the late middle ages, so your sidenote made me grin (and think too much of my paltry knowledge base). A lot of what's considered "traditional" in the West--music, food, religious customs--are also much more recent in provenance than are commonly claimed or thought; it's an interesting phenomenon.

The music sounds really quite amazing. I love the idea of the musicians rustling their scores in time!

The line "opera is like Supernatural; it runs on dead women" made me crack up. All too true, and long remarked on, though I suppose it's more accurate to say Supernatural is like opera, which...maybe gives the wrong impression. Let's not forget Carmen, and La boheme, and well, all of Verdi...I did once see a flamenco opera in which the heroine did not die. There were also lots of flamenco-dancing nuns with very long wimples.

(sidenote: have you read the short story "Fidelio and Bess" by Ali Smith? I rather like it.)