I have truly learned a lot about quilting in the 6 months I've been on this board. Swapping and trying new blocks and getting advice is a great way to learn.
But, my opinion only, I think one of the problems is that the inexperienced quilters try to do something beyond their skill set. Yes, I too would like to outlaw the 9-patch, but know it isn't fair to do so, April. But if one is inexperienced, they shouldn't try to do a complicated paper piecing or a multi-seamed pieced block. And the biggest error of all is NOT MEASURING the block when one has completed sewing. You cannot tell me that they didn't know the block was undersized whn they sent it out!