I will not be confused with an ethologist. But I do know that whenever I try to dance with my honey, and our dog is anywhere near, Jenny gets excited, wags her tail, and jumps on us to join in.
My understanding with what little I know of ethology is, Jenny does so because she understands dancing as equivalent to dogs’ play-fighting. That, she understands; that’s why she wants to join in. So I’d assume that’s the shortcircuit in her brain, rather than understanding dance on its own terms.
Dogs are also hypersensitive to changes in people’s gait. Jenny gets very agitated when she sees me on a swing; but that’s something I gathered from reading, rather than from Jenny. I think the freakout of dogs seeing the changed gait of dancers would overrule any recognition of controlled gait as communication.