I blew one of these dead in my last game of the year - being watched by supervisors.
Except the player was coming from the sideline 2 steps in bounds, instead of not going all the way off.
The supervisor questioned me on it and I said I tried to get the players attention to tell him to establish in the numbers, he didn't react, and I saw no D coming over to cover him, so I blew it dead, 5 yards sub infraction.
I felt good about it. No cheap scores.