I think it all boils down to the pattern was written for 1/4" seams. They say to use 1/2" seams for flannel but didn't adjust the sizes. Someone check my math ---
I think if you cut 5x5, 4.5x5, 2-4.5x8.5, and 4.5x12 it will sew up to a 12 inch square. Unfinished.
Cut a 8x8 for the center and 3" strips to go around (3x8, 3x10, 3x10, 3x12) will sew up to a 12 inch square - unfinished.
When you sew them all together the squares will finish at 11". Hope someone double checks me.
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