I think there are the rumblings of a "movement" to work with skiers that show that condition, as opposed to work against them. Afterall, they are having fun, and that's the most important thing. The last thing we should do is to try to teach something that is completely foreign to their experience -- unless they've requested that of course -- because they just won't come back for more of that "abuse".
No one wants to be anywhere near an implication that they suck. We have to make sure that's not the underlying tone of the lesson, which is really hard when you're teaching the opposite of what they are doing.
I think that one way is through teaching line -- the tactics/purpose/intent. If you choose to do it by setting up a "course" using brushes or builders chalk or terrain features or not do it at all is up to you.
The other is by teaching how to get more performance from the ski -- that of technique.
Oddly enough, speed will dictate they ski a rounder line, otherwise, they'll be dangerously fast. Again, oddly enough, if they can generate more speed on the greens while turning and really feeling the forces, they may stay away from steeper stuff until their technique lets them enjoy those slopes just as much.
I seriously think that we should be focussing on showing skiers how to have more fun on the green trails and the lighter blues. I'm the first to say to the students that those trails are my favourites. They're easy, safer, nothing seems dangerous, my fears don't need to be minded, I can relax and I can concentrate on skiing, I can go as fast as I like and feel all of the forces of the turns without worrying about holding an edge or blowing up.
Look at it this way: when I learned stuff, I started gently and ramped it up slowly. If the student looks up to the instructor, would they not want to emulate how the instructor acheived their level?