Lol, I traced just today. >.> Granted, it was my own art, so whatevssss. XD I trace the crap out of my own stuff.
But anywayyy, I agree completely with Gunz, Cloudy, and friends. But I also agree that it can be bad.
Tracing is kinda a way of studying what you already know visually. You can study for a science test by making flash cards of material you already have memorized. Sure, it won't hurt, but the only thing you're developing is quick recall of things you already know. The same goes with tracing. If all you do is trace, the only things you can draw are the same figures--albeit, you could probably draw them quickly. What good is that when other artists can draw whatever they want from imagination?
Instead of tracing you should advise your friend to draw from reference, either freehand or with a grid. That way the skills they learn can be applied to other situations instead of remaining isolated within the image. Win-win, right?