BagLady, all of the acts you see in a circus are "performances"---all of them. So considerably more than one or two people could have used the word "performance" in their entry--EXCEPT that Sypher ruled the word as invalid after ren's entry. We don't know how many people took this into consideration when posting their entries. Apparently you didn't.
If you really want to get technical about it, you don't see an "Equestrian Bareback Performance" at the Circus--you see the bareback rider doing what they do, but you don't see the "performance"--you only see the performer. This weeks topic--vague as it is--refers to people, animals, and objects you can actually, concretely see.
But, Sypher ruled out the word "performance" early in the week, BL--why did you ignore his ruling? It wasn't just specific to ren's entry--he ruled the word as invalid and made that quite clear.