It seems like every season, especially at the beginning, the Refs are calling a real tight game and sometimes, they seem to be focusing on things that they let go the previous season. Guessing the offseason for refs consists of the people in charge looking at complaints and game film. Deciding what they need to improve on, maybe suggesting some rule changes to the Owners. This year it was the O-Lines and if they were lined up correctly that was under a lot of scrutiny.
Bottom line, coaches/teams need to scout the crew of officials that will be working their next game. Let the players know what that crew generally looks for and will flag.
I will say one thing I absolutely love, is the ability for the "guys upstairs" to call down to the refs and get a call right, before it has to be challenged. A system some of us have been talking about and wanting for years.