On my first cruise the guy behind me at the drill got a call on his cell phone from his father. Seems the old guy fell asleep and woke up and couldn't figure out where everyone had gone! Hello! Do you not hear the announcements!!!
We actually did have to check in at the drill when we were on Disney. We also had to stand in order - shortest to tallest so everyone could be seen by the crew. Made the drill go quickly and I felt secure that my kids knew what to do in an emergency since they could see the demonstration.