Well the private emails are missing and I guess I wasn't clear without the backstory.
The point isn't the fabric that is missing. I think for a quilt washed a 100 times or so (without exaggeration) and being as old as it is, made from scraps when I was poor and cold, it is in pretty good shape. I don't have any acrylic blankets washed that often that survived either. I make blankets designed to be machine sewn, machine quilted and machine washed and eventually to be replaced -- I'm not making heirlooms to last all time. I get bored of them. I rather enjoy watching them age -- did you know that a lot of what you "think" was brown in Civil War quilts was actually purple when it was used??
The point is that all the things about open seams being not as strong as being pressed to the side. Or that they would break. Or that the batting would come out. Dual-Duty thread was anti-quilt police -- for one, it was easily available and cheap and two it was cotton wrapped polyester that would eat through the fabric. That stitching in the ditch would break the seams and likewise, batting would come out.
Nothing wrong with the seams at all -- they are indeed stronger than the fabric but didn't hurt it either.