It took an hour and 15 minutes to correct the wrongly sewed seams on the "raggy" quilt. It had taken a long time to pick out all the seams with a stitch ripper after the first mistake. After the next 5 strip sets were also wrong, I chose the dangerous way to remove stitches.
Start the seam ripping with a seam ripper. When there is about 2" taken out, lift the top fabric, hold the bottom fabric taut and aim your rotary cutter at the stitches that are exposed. Make little jabs at the exposed stitches with the open blade. Just be very careful NOT TO JAB THE MATERIAL, or you will get a nice hole where the seam should be. This is the fast way, and it is effective.
Then take a good pointy tweezers and remove the bits of thread left behind.
Now you're ready to cut the strip into the appropriately sized squares. These are 7 and an 8th inches. The 8th extra is just because that's how wide the strip set is vertically. That's good, because they will be sewed together with 1/2" seams to provide a nice bit of "chenille" at the seam lines.