I am doing the size 12 shirt with the full collar. It seems to me that the collar is about 2 inches too long. Am I doing something wrong? After I turn it (with a 1/2 inch seam allowance) I have a collar that is about 15 inches long measured allong the "collar stand" portion. My neck is only about 12 inches which it should be. I know about the error in marking the sizes of the yoke and I am sure I used the real size 12 yoke. What am I missing?