Ships were supposed to have safety-themed events from time to time. The Damage Control Assistant on one ship, who had the collateral job of Assistant Safety Officer*, arranged for a program of traffic safety. One of his ideas was a hot-dog cookout on the pier, offering free hot dogs and soda.
The catch was that anyone who wanted the free food had to first take a ride in the Convincer. In case you didn't click the link, the Convincer is a gizmo that you ride in; the seat slides down some guides and then slams into some bumpers to give you an idea what a low-speed crash feels like (and why you should wear your seat belt).
The Chief Engineer thought it was a good idea if he rode it first. After being slammed to a stop, the CHENG had a revelation and an idea. The revelation is that the shoulder strap for a seat belt naturally goes over the collar points of a uniform shirt. If you were wearing a shirt that had what the Navy calls "collar devices" (rank insignia), the impact drove the collar device into your collar bone and it hurt.
The idea was to combine the Convincer with a demonstration of why it was a good idea to get a car seat for kids. He told the DCA to have someone get two 5-lb bags of flour or sugar from the cooks, to put them into a plastic bag and to wrap them up with duct tape to make a simulated baby. You'd ride the Convincer, hold onto the "baby" and see the "baby" go flying out of your arms when you jolted to a stop.
That turned out to be a great idea, for it developed into an informal competition to see who could hold onto the "baby". Hardly anyone could.
So the XO came down to make an appearance and ride the Convincer. He got in and strapped in. The CHENG and the DCA were watching. The DCA asked the CHENG if maybe he should tell the XO to put his collar over the shoulder belt. The CHENG smiled and said: "Nah."
The XO rode the Convincer, it slammed to a stop. He said: "Kee-rist, that hurt." afterwards and rubbed his collarbone. But he didn't drop the "baby"; it spun out of his arms and he was able to catch it.
Oh, and when the Captain rode the Convincer, the XO didn't tell him about the shoulder belt.
*That was true for all ships. The DCA had the collateral duty of serving as the Assistant Safety Officer, the Chief Engineer was the Safety Officer. They did those jobs in their copious spare time.