I can certainly relate to what you are experiencing. All patterns are just not exactly correct. The block I'm making at present is comprised of many pieces and I've measured down to the last thread. I've starched, pressed, prayed and when I went to put one unit together it quite obviously was going to be too small to fit with the rest of the units. So I made the decision to change one HST's size and voila it worked. The pattern is one I will definitely make again, but I've made notes like crazy. So I guess what I'm finally getting around to saying is, blame the pattern. Don't beat yourself up, the designers of patterns are only human - granted they have talent, but they can make mistakes too.