In the early days of the contra dance revival, we were happy to just get out and dance. Most dances we did were traditional choreographies that had been around, in some cases for hundreds of years. After awhile, people started writing their own dances and their own tunes and the revival completely reconstituted into a living tradition. This inevitably generated an interest in harder dances, more complexity and the rise of 'experienced dancer only' dances. I've long been impressed by how the contraphile generation pretty much mimicked an earlier generation's progression from traditional squares into Modern Western (or Club) Squares. Here you'll find some people speak to this phenomenon.