In response to the questions about the duvet cover: I have an old comforter that I want to repurpose. The fabric and color no longer work. (It was originally for my young daughter's twin bed.) As it is a high quality comforter, I thought I could sew a quilt top, and make it into a cover for the old comforter. I make so many more quilts than I can use, I thought I would make something that would have a specific use, and still get all the fun of making a quilt top. So, I pieced the quilt top in the picture above and lined it with Kona solid white fabric. This will be the top of the "sack". I had left over fabric that I made into a simple strip quilt for the bottom of the "sack". It is also lined with Kona solid, and I quilted the strips on the seams to hold back quilt to the solid "lining". (So I wasn't worried about the seams or amount of quilting on the back). I need some sort of quilting to hold the Kona 'lining' to the quilt top. I will sew the two sections together to make a lined sack. Then I will put the old comforter in the sack. I need to determine how to finish the closure. I plan to do buttons, but may end up with Velcro or ties. It will be mostly decorative on a guest twin bed in my sewing room so it will seldom actually be used. I hope that answered the questions. My concern was how much quilting would be needed to secure the pieced top. Is quilting's purpose only to keep batting from shifting? Or to better secure the pieced block seams? Sorry my original question didn't make sense.