Keith Relf is really interesting to watch, riveting even. Same for Beck Samwell-Smith. Relf's stage presence is totally original and his harp is excellent. It is nice to hear an alternate to the earlier Clapton version recprded for their debut single, though I'd have to revisit the earlier version to note any difference guitar-wise. There's another (highly recommended) video from this show where they cover I'm A Man and where you get to see Dreja on the maracas, Relf on the bongos and Beck setting his Tele upright on the stage prop so he can freely bang around his slide for effect during the (mini) rave-up.
The Yardbirds were the epitome of cool, if I may say so. Particularly with Beck in the band. Relf had the look and the band members had the chops. If they had been managed better they could have lasted longer. They should have lasted longer. I ran across Led Zeppelin's "The Song Remains the Same" concert movie the other night. The band was doing a way too long version of Moby Dick, which, of course, is a thinly reworked version of the Yardbird' rendition of I'm Not Talking,