I have done quite a few SITD quilts. I too go out of the seam. Sometimes I am able to use Micron pens in the correct color and go over the missed stitches. Obviously, they are not meant to be judged. Just loved. I have tried several different ways. It takes constant concentration and I am not very diligent in that area. When possible I use a wavy pattern (stitch is on my Brothers' machine). It moves approx. 1/16 inch away from the seam in both directions (left side and right side) and is about 5/8" in length. I just finished quilting a quilt this way. I did straight SITD on the white fabric but used the wavy line on the dark fabrics. I used matching thread. Hopefully, you are able to see the stitching in the second photo and then the photo of the backing.
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