I just LOVE Jim Carroll's story about the pot under the floor - that's going in my programme!
Re all the different cultures doing step-dancing: I see a lot of similar movements - which is probably why some put it all down to copying sean-nos - but, on reflection, our legs are all built the same way, so, wherever the dancing comes from, I suppose it's going to end up looking similar.

However, I'm not going to say this is the result of exhaustive research, but, looking at maybe a dozen and a half videos on YouTube, I've noticed that the step involving lifting one leg and crossing it over the other seems to be unique to Scots (Cape Breton, Scots-Irish, Appalachian), Irish, and French Canadian dance. Welsh and English clog dance uses pretty much the same steps but not that one.

On the other hand, Welsh and English seem to have a step involving throwing one leg out to the side that doesn't seem to be a common feature of the other styles - it was more like something from modern tap.

Has anyone with more dance savvy than me noticed any such differences among the North American schools of step-dance?