The "Vet's" will correct me if I'm mistaken, but one thought about the skier/boarder conflict's seen from a NooB's perspective,..
I've noticed that it seems the experienced, "adept" skiers I see are heading down the blue & black runs with a lot of speed, but unlike the "once a season" skiers, they are flyin' & maneuvering down these runs within a fairly narrow corridor! ......
I agree. The adept skiers are very fast, make very little friction noise on the snow too (way less than riders), and use very narrow S's to literally stream down groomed black diamonds. These skiers tend to use longer skis for the purpose of skiing very fast as well.