But not everyone agrees. “I bought this pillow for the long-weekend holiday trip. The memory foam is the perfect firmness, and it is so soft and comfortable,” says someone named Ivan in an Amazon review of a neck pillow similar to that which failed me on my recent flight. Okay, Ivan. Someone named Allen says, “I use this in the car. I fall asleep very easy. This keeps my neck comfortable and I don't wake up with neck pain.” Okay, Allen. Someone named Cass says, “I returned it as it had a horrible chemical smell, plus whatever was inside was a solid piece. I wanted something that had little pellets.” Well. This one seems like more of a “Cass” issue, actually.

Brad John, the cofounder of Flight 001, a popular chain of travel stores about which Martha Stewart has allegedly commented, “I love this store, it looks like an airplane,” told me the U-shaped travel pillow sells very well, even though there hasn’t been much innovation in the market. “They’re basically the same as they’ve always been. We sell the heated ones, the inflatable ones, the foam ones.” The main advancement, he said, and the top seller at the moment, is a convertible travel pillow “which you can either make into a regular pillow or a U-neck.” Very interesting that the top-selling U-shaped neck pillow is one that has the ability to function as a normal, non-U-shaped neck pillow.

Brad John himself uses a normal pillow on flights. “I just don’t find the neck pillow comfortable,” he said, “but that’s just personal preference.”

Everyone I spoke with agreed that the U-shaped neck pillow stinks, notably my friend Megan Reynolds who said, “We have one in the house but the boy cat uses it for sex.” My friend Lindsay Robertson, to whom I was referred explicitly because she regularly uses a U-shaped neck pillow on flights, proved to secretly be a member of the U-shaped-neck-pillow resistance: “I never actually use it as a neck pillow, because I can't sleep that way—I'm not sure anyone can,” she told me. Instead, she puts her neck pillow on the tray table in front of her, takes off her glasses, puts her hands in her lap, and “[lets her] face fall completely forward into the pillow, as if [she has] expired.”

What accounts for why some derive comfort from the U-shaped neck pillow—(liars)—and some do not? I asked Mary O’Connor, who is a professor of orthopedics and rehabilitation and the director of the Center for Musculoskeletal Care at Yale. “I’m unaware that there is any clinical data that shows they’re effective in reducing neck strain or neck discomfort,” she said, “However, many of us who travel have experienced falling asleep with our neck in a weird position and it bothering us thereafter. So, I think they can be helpful, but that depends on how they’re used and whether they support the neck.”

The ideal pillow, she said, would keep your head and neck in neutral alignment with your spine, so you’re not too far forward, or backward, or too far to one side or the other. “But how do you know, when you’re in the airport, that the pillow you’re going to purchase is going to give you the right support?” O’Connor asks. “The pillows are all the same. Some people have short necks, some people have long necks, and there’s no ability to look and say, ‘I need this design or this size pillow for my neck, to really work well for me.’ And that’s part of the challenge. Could one of those pillows help someone? Yes, they could. Will they help everyone? Probably not.”