A couple small corrections to my previos message about diagramming: I wrote That should read "... a duple improper contra ..." I also wrote: Actually there are many single-progression dances where dancers move on from one set of neighbors to the next partway through the sequence rather that at the transition from B2 to A1. (By "B2" and "A1" I refer here to musical phrases, not to couples in my diagram notation!) In those, dancers 1 and A dance part of the sequence with neighbors B and 2 and the rest with neighbors D and 4. --Jim