Some other end effects:
Switching roles in unequal dances, like Brimmer & May Reel.
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There's also the more subtle effect, like that once you swap roles,
every swing is on the other side, every swing ends facing the other
way, and every progression is 180 degrees the other way.
This gets people, and it can be helpful for experienced dancers to recognize it.
(Example: 3/4 hey then swing partner can turn into 1/4 hey then swing
partner by accident.)
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Also, there's some dances where you have to re-enter indecent, with
the woman on the left, man on the right. If the dancers waiting out
force the people to adapt to them, those same exact dancers will get
spit out again, over and over, until an assertive dancer overrules
them.
(My rule for this: "Do what the dancers in the dance need of you.
Adapt to them -- they're more in the zone.")
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"Scooter" by Tom Hinds has an unusual case where the men have to
double-progress around the end during a single ladies chain.
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Some of the unequal dances have rings of one or three, depending. See
"Fiddleheads" for a good example.
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Finally, there's a few dances (like "Falling in Love Again") where
there's a ladies chain on the left diagonal followed by a chain on the
right diagonal. The only way I've found for neutral couples to survive
is to wait out improper, so they can be on the sort-of-half-diagonal
chain in both directions.
-Chris Page
San Diego