May I suggest that in devising new dances, the goal is to invent something
of great and lasting value. With this objective in mind, then the music
is of paramount importance and the new dance should be devised to fit the
musical phrases and style. Thus formations requiring 8 bars of music
should start and end with the 8-bar musical phrase, etc. In my
experience, dances including formations and musical phrases that do not
match are generally not danced very often. For example, 3 bars down the
middle and back up the middle for 3 bars does not fit the music.
Consequently it is rarely done correctly at an evening dance even though
it may well have been taught precisely. Matching the dance to the music
can be done exquisitely, for example, if bars 1-8 are repeated in bars
9-16, then the 8-bar phrase of music can be repeated rather than going on
to the next part (e.g. in Machine without Horses). I hope this helps with
devising new dances - Good Luck.