I think part of the reason for using Minky on the back of a quilt is the additional "coziness" and softness of the minky fabric. I have used Minky and did ONLY stitch in the ditch to preserve the fluffiness of the minky. All over quilting would stitch down the fluffiness and kind of defeat the purpose of using that fabric for the backing in the first place, especially if that all over quilting was too close together. Just my humble opinion.