there's another post on this (that i hijacked, i'm afraid) on which i said that i don't see why you can't make the strips (either the top one or the bottom one) be strips, or piano keys, or solids. i would think that as long as your top and bottom strips are the same width, for example 2.5", and they re stitched top and bottom, it will work.
somebody else, do it for me. i'm too lazy.