Waves of Prog?

I've often seen people talk about periods or waves of prog. In my mind, there have been about five, the proto prog of the 60s, the 70s golden age, the neo-prog revival from about 1979-1987, the post-prog of the late 90s and 2000s (including Porcupine Tree, the Mars Volta, etc.) - which also sparked the rejuvenation of a few neo bands (eg, Pendragon with the Masquerade Overture and IQ with Subterranea - though, to be fair, Pendragon never really stopped), and lastly the new/modern prog wave we seem to be on the verge of (including Thank You Scientist, Steve Wilson, etc.) - while, at the same time, several of those neo bands that came back in the late 90s are experiencing a golden age, eg. The Road of Bones and Resistance by IQ and Love over Fear by Pendragon all released fairly recently (for prog, anyway)  are now widely considered masterpieces.