Many have highlighted that the dance video which appeared spontaneous was actually well-rehearsed.
I am not concerned that this is the case. Some of what appears most spontaneous in a drama, stage-production, stand-up comedy, busking, and so on, has actually been extremely well-rehearsed. Presiders at liturgy, others taking leading parts (readers, prayer leaders,…) need to rehearse to the point where what is “fixed” (responses, readings from scripture,…) is as “natural” as what is not. This is central to my using language as a model for liturgy.
Anything from Improv Everywhere.