I don't know but that is my impression. The NSAA rules mostly cover the same stuff, albeit without mentioning carving skis and snowboards.
Not sure what you mean but maybe we are arguing semantics. I agree it's foolish to consciously assert your "rights" as a downhill rider and keep carving if you know there is traffic above you. If I perceive there is any possibility of being hit from behind I simply pull over and sit down, or stop carving.
But that still doesn't cover me 100%. Just today I was carving down a low-angle runout trail back to the chair, not taking up even a third of the trail width, thinking I was all alone. Suddenly I was overtaken by a group of 3 park skiers - you know, the kind that practically straightlines everywhere but in the park. They avoided me appropriately and comfortably, but I was not aware of them until they were next to me. I don't think I did anything wrong, and if one of them had hit me they would be 100% responsible.