I went through this morning and while not a total cluster...it was a pain. They were sending all these novice travelers into the line. None of whom could seem to figure out what to do. It was like being in a regular airport line circa 2000.
Let's admit it--we liked pre-check b/c it was an exclusive "up in the air" club of uber-FFers who all knew the rules, the system and want to get through really fast. It was the closest any of us have to having an actual airport ID. Seems the party is about to end.
No dog though.