In my post about the "Seventeen Year Itch" episode of "Beverly Hills, 90210," I mentioned that when Jim changed into his pajamas, he kept his underpants on inside the pajamas.
Struck me as odd (other than as a way of preventing the TV audience from seeing Jim's junk). But reader Annie asked in the comment section if it is "standard for guys not to wear underpants with pajamas?" She added: "My husband's not a pajama guy (Texas is way too hot for that), and I guess I never thought about it in general."
So I'm asking: What is the proper approach to pajamas, and sleepwear generally? Please try to phrase your answers tastefully.