I agree that your cutting is more likely the culprit. I know I have those issues myself especially if I do cutting over various times. Such as - cut x number of pieces/fabrics on day 1; next pieces/fabs day 2; etc. Day 1 I may line up the fabric on this side of the line on the ruler; day 2 might but the other side of the line. Usually nothing a little stretching or squishing can't accommodate, but still... But I also agree with PenniF...relax. You should not make yourself crazy with perfection. Especially on 'normal' blocks. If you're doing a really fiddly/precise block, you may want to jump in to paper piecing. It can make those really pointy blocks work perfectly.