I know with some effort you can do some truly interesting things with multiple tracks in VV3. I was wondering if you can mask and or apply effects to a moving target so to speak. For example everyone's seen where faces or license plates are hidden on shows like COPS by just having some crude smearing for lack of a technical term. This could have real world use like removing the unwanted uncle Eddie from the backgrounds in weddings or maybe applying some video plastic surgery.

Can anyone offer insight on how this is done? Am I wrong in my guessing it is a tedious process that needs to be done frame by frame in something like Viscosity?