To me, the biggest issue on a swapped block is WHERE is it off? If the block doesn't meet the size requirements then don't send it. If you have something that is not perfect on an inner piece of the block but it is square and correct size the question becomes if the error is really obvious.
I must be the quilting police. I'm an absolute beginner and don't know how to deal with blocks that aren't big enough or square. On that same note, I always try to send the best block I am capable of making. Sometimes that means making a second block (it may or may not be the same pattern) and sending both.