I see all these ways to fix it and I think to myself....how is mine staying straight because I seem to be doing every thing that is listed not to do? I do all my bindings as bias. If I have a lot of seams on the edge of the quilt, I will stitch a normal 2.0 stitching line around it to keep the seams from separating. I snug up my bias binding as I sew it on. Not stretching it, but making sure it fits snugly with no extra wave and I use a 1.8 stitch. I have never had any problems with my quilts. However, if I cut the bindings on the wof, I have a mess. It waves and I actually get wrinkles in the binding. That's why I converted over to bias bindings. They have been a success for me. No amount of ironing, fitting or anything will keep the WOF bindings flat and pretty.