This is an excerpt from an article written by Jay Mohr for Parenting Magazine.
"Suddenly I was jealous. Nik had peed in a diaper and I hadn’t. I leaned against the wall, trying to will out a stream. When I was finally successful, it was euphoric. No wonder Jackie had given us such a hard time about being potty trained. Peeing in a diaper is a freaking awesome experience! To my surprise, it wasn’t wet and disgusting. The diapers were amazingly absorbent, and whatever pee came out of me magically vanished into the lining."
Evidently, while his son was at a grandparents he and his wife tried on and used adult diapers to find out why their son was refusing to potty train.