I agree with the accuracy. Do it until it is right. Buy extra fabric so you can cut out some new pieces if you need to, because if it has been ripped out more than twice, your block will be distorted. You WILL have blocks where this happens. Don't think (like I did) that it will magically come together, because it won't. To compound that, my first quilt had sashing and the fabric I chose had virtually no give. There was much wailing and gnashing of teeth the night before my class when we were supposed to have our top finished.