Tom O'Horgan was the man who originally directed HAIR on b'way in the last 60s. He later also staged JESUS CHRIST SUPERSTAR, though I don't think he took a book writing credit. Tim Rice shaped the arc around the Holy Week story, and as you know, there is no spoken dialogue. That's all Rice, and he did the same with EVITA (with a lot of input from Hal Prince when the EVITA concept album became a stage show...) Unless I'm wrong, JCS had already been done, more in a concert style, in London's West End. O'Horgan was the first to stage the show full-out, and gave it a surreal, sort of timeless look and feel; the act curtain had everyone crawling over it during the overture, and there were post-modern designs that looked like something out of the ALIEN movies. I think you're right to miss his hand in contemporary shows. Alas, I also think he died. If anyone knows when, please post. Original minds like O'Horgan's don't hit b'way very often.
"I'm a comedian, but in my spare time, things bother me." Garry Shandling