not sure how my feather bed works

I have four down feather beds that I bought from the Company Store 20 years ago and haven't used since, partly because I never understood how they worked. They are like two comforters stitched together: One is square quilted like a regular down comforter and about the right size (twin in this case) and then attached to it is a similar sized but much much puffier section that isn't quilted at all. It seems as if you are supposed to sleep on the non-quilted section and then throw the quilted section over yourself....but that doesn't really work. Has anyone ever seen anything like this or have any advice? And yes, I guess I could separate the two sections but they must be connected for a reason. Thanks!!