I just finished a project that used fusible interfacing. It said to cut the fabric 9x12 and to cut the interfacing the same, then fuse. I cut the interfacing to 87/8x 117/8 (undersized by 1/8") I will be doing this all the time now. Less chance of the fusible getting on the iron and it will still be caught in the 1/4" seam.
piney