Regarding the call for a penelty with no time left on the clock: How many times have sports fans screamed about Refs injecting themselves into a game preventing the game frm being decided on the field? This is one of those case where the right thing to do was to non-call.
Techinally Holding can be called on every play, yet a discretion measured by fairness is what we all want. This spirit is why the non-call is the right thing to do.
Not wearing mouth-pieces every play
Coaches stepping onto the field
Chin Strap snaps not in place
Offensive Linemen moving their heads while in a down stance
Helmet stickers on UNIforms
Non-calls are a wanted and needed institution of the game.