We are stumped by the suggestion that perhaps some don't use a fitted sheet. Are people out there really working with two flat sheets when making their bed?
On the other hand we will say that, while this note seems perfectly obvious to us, we appreciate the tip regarding the top sheet going wrong side up. (That way when you fold it back over the blanket, the right side—the decorative, printed side—will show.) We are surprised how many folks don't know that.