Why are beds flat?

Last month in a Swiss hotel, I came across an idea so beautifully simple that I felt it would be immoral of me not to share it. The bed in our room, rather than having one king-sized duvet, was covered by two double-size duvets overlapping in the middle. Eureka!

Given that the Swiss are world leaders in conflict-avoidance, it seems likely the idea originated there, although I have since learned the practice is also common in Scandinavia. Back in Blighty, when one person in a double bed rolls towards the edge, they take three feet of duvet with them, leaving their partner out in the cold. This typically leads to retaliation and often escalation. The Scandi-Swiss system, by contrast, creates a buffer, a DMZ of surplus duvet, which means that bedding fights are no longer a zero-sum game.

Why has this approach not been adopted more widely? The question led me into a rabbit hole of research into bedding innovation – during which I discovered that in the 1980s as many of 20 per cent of US households owned a waterbed. And that the first one was salaciously marketed as The Pleasure Pit since, despite many downsides, waterbeds are apparently far superior to conventional mattresses when the occupants are both (or possibly all) awake.

The reason this topic interests me is that for years I’ve believed the whole premise of the bed is wrong. And here I go right back to first principles: I don’t think beds should be flat.

Anyone who has fallen asleep on a sofa and enjoyed a surprisingly good night’s sleep with their arm draped along the backrest or behind a cushion has had some intimation of what I am suggesting.