A very weird question about Australian Shepherds and what I call the "Aussie Scoot"?

Ok, this is a weird question but I want to see if anyone else's Aussies do this. We have an Aussie that all of his brothers and his mom do this and it is hilarious as he** to watch. When our Aussie goes outside to do his business he starts to poo in one spot and slowly moves around in an elliptical pattern as he goes. We call it the Aussie Scoot. I wanted to see if anyone else out there has their dog do the same thing and if there is any genetic or historical reasoning behind it. Thanks!