If you look through the gallery, there's a good mix of square and round. Not sure, but I think the Yard and Swamp often use similar blades on their releases--9-11 is the same shape as the Rodent 9 for instance. Maybe it's to help differentiate the different companies with similar releases? That doesn't really hold up too well considering the M6 and Scrapper 6 both have round choils...
Dunno. Maybe just to shake things up and get us posting crazy threads? <img src="/ubbthreads/images/graemlins/wink.gif" alt="" /> <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" /> <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" /> <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" />