But it's not obvious who everybody is in the studio. Some at any rate mimic and dance at the side. When not dancing most dancers seem to constantly check their understanding of the moves - more use of the universal counting with hands and arms. Sometimes they mark with their legs as well. They also gaze into the middle distance, glaze-eyed, at the same time.
Dancers talk to dancers in the same piece, second cast has the odd word with first cast.
If there is a lull, dancers thinking of another part entirely will consult with the notator or each other. But a couple of seconds of dance seems to require several looks and checks. The others shuffle to the side. Most are wearing big plastic knickers outside their tights. Whatever, the knickers make them look slightly surreal.