I think just freestyle dancing is a good way of judging someone's dance abilities, but it all depends what the aim/contents of the workshop is. And it depends on who's attending the class, too. I know that if someone observes me dancing with a beginner/intermediate to music I don't like, I will look very different from when I dance with one of my favourite advanced dancers to music I love.
So, in your hypothetical critique workshop - would it be people of all abilities, or divided into separate levels of dance ability?
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