Another question for the pros; given the nature of the submission process, and the knowledge that your original submission probably wouldn't be used, did you ever try to come up with a storyline just for the purpose of the submission, maybe one you weren't too fond of, so you wouldn't get emotionally attached to it?
Good question, but no. I always hope to write any proposal I submit. I'm just realistic enough to know that there's never any guarantee that it will sell as written. And I'm flexible enough to switch gears if an editor says "Forget ENTERPRISE for the time being. I need a VOYAGER outline . . . ."