>I have two Sly bootlegs from 1968 from The Filmore East and
>the music presentation in Summer Of Soul matches
>the set he used to do. All the way down to the crowd
>interaction on "Higher".
>This was my first time SEEING it though, and it was great to
>see. The shows I have are just under an hour,
>so I imagine Sly & The Family Stone did maybe 20 minutes.

The "Higher!" portion of the show was indeed a Sly standard all through that era. It capped off, and is the most famous part, of their Woodstock set too. If you think it's crazy seeing the group do it in front of a crowd of 50,000, imagine a couple of hundred thousand.