This is from (I think) 1969 with Peter Banks on guitar instead of Steve Howe. It indeed rocks hard, and Chris Squire's bass playing blows my mind. The harmonies at the end are beautiful and Jon Anderson's final note is so powerful! Love it...
Yes was a lessor band,though still one of my fav's, without BRUFORD. He is the guy making it rock hard.
I just saw Jon Anderson. Yes seems to be greedy as they replaced him with an identical sounding singer due to past health issues.
I won't see Yes without him and he puts on one hell of a solo command performance. Flawless.