I do it regularly. I keep a V3 on a stand that I put in front of my bedroom mirror up close. This way I can stand and walk back and forth in semi-circle getting great angles of the inside an outside of each hand in action. Really helps trad grip with the different techniques in use simultaneously. Good for learning about height, control, even dynamics amongst other things.You know I have never done the mirror thing. It does seem like it would really help in training your hands to execute certain techniques. As we all know, you can never have to many points of view so yeah it makes sense.