My concert count is at about 75. One of the Austin shows had to be cancelled due to an eye infection or injury that Clarence had. They made it up later that same tour.
I didn't realize he was almost 70! I did remember he was older than the rest of the band, but wow!
The thing about CC was never that he was the best technical musician (and that's not saying he wasn't really good). The reason he was integral to the band was the his style brought a swagger, an attitude to the music. That to me was what the band was all about in its heyday, and even now to some extent.
Between that and the rapport he had with Bruce, it's really hard to see someone replacing him.