I would think that video taping practice sessions would actually be beneficial, ain much the same way as MahlerBrass mentioned.
In my professional life (which gets in the way of my practice time WAY too much
) we sometimes video tape our practice sessions for presentations. It helps to catch some of the bad habits that we don't even realize we are doing....like putting our hands in our pockets, licking our lips, etc. etc.
Video taping would be a good way to see ourselves as our audience sees us.