64-bar and 48-bar dances are problematic because of the piece count. Basically it's the phone-number problem -- short term memory works best remembering a maximum of sevenish-eightish pieces, or chunks. Above that the dancers need to concentrate harder, or be reminded, or redefine a chunk. (Make swing-circle-swing an entire chunk, for instance.) I find that's a problem with most of the 48-bar dances I've run across.
I've only danced one 64-bar dance, and there the caller never dropped out. It was at a dance festival. -Chris Page San Diego
