I think there's a valid argument that the highpoints of Moving Waves and Focus III are higher, but this seems a more even album overall.
That clip was for a BBC In Concert. They were a popular band in the UK and made various TV/radio appearances here- Live At The Rainbow was actually broadcast by the BBC on TV show The Old Grey Whistle Test. This is the show perceived to have launched them in the UK after a studio performance of 'Hocus Pocus'.
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