It comes from two things. One is the what they are allowed to do for certification to receive a vin, the other is turning radius. My 36 foot Super C turns like it is a one ton dually because its wheelbase is close to one. It allows you to get into most normal locations. The tailswing has to be accounted for on occasion but really isnt the big deal it seems like. I actually like it when towing a trailer because it gives me more trailer control.I’ve never understood it on most Class C’s easier. Probably onto something about easier to use factory wheelbases.