I almost always do a little piecing on my quilt backs, even if I have the wide backing because I think it adds interest to the overall quilt. It is a great way to use up leftover blocks and other fabric scraps. I have not had any difficulties quilting through the seams on both sides, and the ones I have sent to the long arm quilter have come back great with no complaints from her either. Here are a few examples of some backs:
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