It's oddly interesting to notice two people doing the same thing differently.  To get into work, I have to pass through a gate where people check my ID.  I don't mean this in a bad way, but the people who check my ID are like robots:  They just do what they're told.  They sometimes know why they're doing it, but sometimes they don't.  It's interesting to watch this being played out.  Some guys take a quick look at my ID and pass me through.  Other guys look more closely.  And still other guys look at my ID, turn it over, and hold it up to my face to make sure the picture matches my face.  I find it hard to believe that any of these guys got their instructions from a different person.  They were all told to do the same thing, but some guys took it literally while other guys took it slightly less literally.  It's like a psychological experiment.