(I am posting as a guest because of cookie troubles)

Dancers just need the four measures or four counts--wheter the song comes in 12 or 16 bar sections doesn't matter to them--and actually, the most rock dancing really came from jitterbug/swing/lindy, and that music is typically 12 bar blues--

Just as a point of reference, Markf revived this thread because he wanted to play some blues on his dulcimer--how he is going to play major sixth and ninth and thirteenth chords on it will be interesting to see--