I don't have time to read all the replies, but as an avid handquilter (over 35 yr. experience) that never machine quilts, Yes, you can easily quilt over seams. Just remember if you stitch-in-the-ditch, quilt on the side where the seam is not. (The low side of the seam.) You do want to avoid extra layers. Also avoid quilting where multiple seams come together. You can send me a private message if you need more advice.