I subscribe to the theory by Mary Ellen Hopkins who wrote in at least one of her books, that the 1/4" on one foot might not be 1/4" on another - so she opted for PPM - personal private measurements. In other words, if you are sewing a consistent seam throughout the quilt construction your quilt will be fine. Personally, close enough is good enough for me, especially since I sew all the blocks on one machine, then I will square up the blocks to the correct size. I hope this makes sense.