Lots of fabrics have looser weaves these days. If you run your fingers down across the cut line while the fabric is on the bolt, and it starts fraying slightly, then I would be cautious and at least know you have to treat the fabric differently.
If I just loved a fabric and was determined to use it, I would probably upsize my seams in that quilt to all be 3/8". This will give room for securing those rogue, fraying pieces of fabric without compromising the quilt. You still might have to double stitch some of the seams or use a pinking blade or scissors to cut back on the fraying, but at least your quilt will stay together.
And yes, even though I do my own quilting, I do cut off all those unsightly, long pieces of fraying fabric threads. They do show up under the pieced top when you least expect them to and I can't leave them showing. It is so much easier to take the time to cut them off.
Last edited by Barb in Louisiana; 11-17-2019 at 08:26 AM.