It would have been better for a reader, if you could just give a little two-three line introduction about the performance and the characters you have described like from where did you pick up the piece, when and where was it performed.
Also, the first paragraph could have been better if you could just add a little more description of the surroundings along with the description of the positions of the dancers which you have done really well.
"Their upper bodies appear heavy, with the curves of their arms mirroring the curves of their backs 'are' they dip down."
Maybe you wanted to put 'as' instead of 'are' in the line above. It is a silly typing mistake to point at but I just wanted to include it.
I really liked the way you ended the concluding paragraph. The rest looks good to me. I hope I could give some useful feedback.