My thoughts on the outcome would be a little different. I think that even when L&C were broken up (Contact, WIEAK & JSN), they were still talking, even if it was a bit strained. Lois was very aware of what was going on with him -- remember, in WIEAK, she scrambled to go along on his rescue, even though they were fighting and in the most distant part of their break up. Even "apart", they were very "together".
Thus, I think Clark would seek out Lois's advice on the tests. She is the other part of Superman (the brains, as Ching would say; "Lois, no helping ..." <g>) It absolutely would add a fascinating twist on the story to have them not be planning their wedding, but I think it would still be terribly hard for Clark to leave her (and his family, friends, job and ... well, his planet) and he wouldn't just disappear without saying goodbye, or even make his decision without talking it out with her, even if it was just as his best friend. Lois has always been Clark's sounding board, even when they were just co-workers, and later, friends. She's also the only one besides his parents who know the secret, and thus, he'd need her help to explain his absense, even if they were no longer dating.
Anyway, just my $.02 worth ... you asked for opinions and that's what your set up made me think of. I think it's really neat twist on the story arc, though, and I hope, however you choose to tackle it, you have fun writing it!
Kathy
