Oops!! From my earlier comment, delete the following:
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"Your dance can be made single progression by using rights and lefts on the
1/2 diagonal (
https://aptsg.org/Dance/dances.html#RL ) , in which case
the robins move 3 places forward and 2 places back. Work out the details
with coins or pencil & paper if you wish.
Your dance is also single progression if only one of the chains is on the
1/2 diagonal"
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It's all wrong