Well, there's the must have the newest most best syndrome. I haven't transcended it, but have learned that good enough to use means just that. Beyond good enouth its all fine points that I usually miss completely.
As for operator error, I've learned that when results aren't as desired the cause is almost always me. Almost, I have a Perkeo II with Color-Skopar that I've never ever got a sharp shot with. I have though, got some fine slightly soft shots that I thought good enough to keep on my desk at work.