Yeah, what you guys said makes sense. I've been able to do a parallel turn (complete with hockey stop when needed) on skis without metal edges. I've also been able to do a nice telemark turn with the same skis. In both cases, I was on a ski resort, where they had groomed it (not track grooming, but snow cat grooming). In sloppier snow, I have to just point and go (even snow plowing can be difficult).
I think Bob makes an excellent point, though. Folks design skis for different markets. The market I'm interested in is relatively small (the lift market is huge, and the groomed cross country market dwarfs the touring cross country market). As a result, I don't think they make skis that carve well without adding metal edges (whether you want them or not). I think it is possible to make such a ski, but I don't think anyone has done it. In general, the ski market is fairly conservative — folks knew about the importance of side cut for hundreds of years, but it wasn't until recently (the early 80s) that companies starting incorporating really big side cut. I think snowboarding drove a lot of that (although there was some simultaneous experimenting going on). I know little about snow boarding, but I'm pretty sure the early models didn't have metal edges. It seems to me that it wouldn't be that hard to make skis in a similar manner. Of course, I'm not sure how much weight would be saved by skipping the metal edges, I just assume it would be significant.

