I've had difficulty with this, too (I'd say I'm camped out here, but not quite a permanent resident). At any rate, what I've found is that generally I don't have to be a stickler about it. In other words, if it's not absolutely perfect but pretty darn close, then "pretty darn close" is good enough. (At least, this is usually the case when I'm a stitch off on the shoulder seams.).
Of course, this is also the person who has trouble using a simple stitch counter. (Am I counting the row I just finished or the row I'm on?) SIGH!