I just finished an 80 x 80 inch quilt for my son with flannel backing. Prewashed and pressed with a little Maryann's, pinned about every 4 inches. Did stitch in the ditch, free-motion, per Leah Day.com. Then more free-motion inside the blocks. I have a Pfaff with IDT but didn't use for this, of course. Anyhow, had no problems with bumps or gathers. I think Leah's site has very helpful information. Check it out. I hope any of this is helpful for you! Keep on doing your own quilting, it is great!