Evening Three Step That makes more sense. It's currently known as an Eva three step in Scotland, but evenening actually means something..

The main progressive dance I recall, was the "Barn Dance", done to schottische and march tunes by large circles where couples would form for only 16 bars and then separate. For some reason, this is the Canadian barn dance to us....

Trusting any one source isn't sensible on this, as it's all open to intrepretaition. Fort instance, the general thinking on the Anglophone country dance is that it is a corruption of the French contre dance, and not the other way round as quoted above.

And as for dances moving about, modern dance festivals really don't help matters. You put a dozen different dance sides together for a week, and you find Country A is doing steps from Country B, in Choreography from Country C to Music from Country D. This is normal, but the national drinks of A to H tend to be involved somewhere.