Timeout to vent - among other things

[Jurassic Referee]

Originally Posted by TheOracle

I'd still wonder if it was absolutely necessary at that point to tell the guy he had to sit down. I'd not have known that the assistant, who would now be the head coach, would have the seat-belt rule. Glad I was not there!

Yes, it's necessary to tell the assistant coach that he's seatbelted. It's the same as telling the head coach. It's part of the penalty and it's the proper mechanic.

You tell them when they're seatbelted so that you (hopefuly) won't have to nail them if they get up and wander. If they do want to get up and wander after being told, then they have no excuse when they get nailed for doing so.