Here's how it works - looks like a normal bed, right?
But check this out:
Yep, that's the convenience of a duvet inner, with a top sheet to protect it, and a super lightweight bedcover over top to protect it on the outside. You only need to wash the sheet, and don't have to wrestle with that gigantor of a duvet to try to fit it in a cover. For us, it's a win-win - plus, I love a white bed.
The yellow Dwell Studio cover you see on the end of the bed in this pic is American sizing and too big for our duvet inner, but it fits our comforter perfectly so is used just for that.
Hope the tip is useful!