On the lighter side, maybe this is how any mushroom loving audience could get enthusiastic about a piece that takes 639 ears - oops, that years - to play!
(No offense to Saint John - he doesn't strike me as a hookah-smoker by any means).
As to WHY he wrote the piece, maybe it has something to do with the number 639 itself? Numerologically speaking, being a multiple of the 'sacred' number 3, and the mystical transformative 9, it's a pretty creative and powerful number. Wonder if John was into the metaphysical side of life at all - does anyone know if he was that type?