Who was the most progressive of these classic prog rock bands. Inspired by listening to ELP's giant triple live album (you know the one) in rememberance of the astonishing Keith Emerson, and thinking they really might have had the clearest handle on prog rock's traditional ideals, a seamless and authentic blending of jazz, rock, classical, and other genres, with thought provoking and/or fantasy and science fiction lyrics. Now my sig says my answer, and I do stick by it, but Rush were only the most progressive IMO because they progressed beyond the traditional constraints of prog, if that makes sense. At their most traditionally proggy, I think they were only equal in progginess to these other bands. What do you think? And if I missed anyone major, please tell me!