Most people never reinstall their OS at all, so this is analogous to saying that you shouldn't be worried about what can go wrong with doing your own wiring (to use someone else's example) because, after all, you could just rebuild the house.

I expect going into Gnome or KDE and resetting the settings for xfce would have also worked. Though frankly I didn't bother -- if an experienced Unix user can break it in 10 minutes without trying, it clearly isn't stable enough to use.