Well, my point is just that X/1999 characters are over the top. They don't move on in terms of romances and their romantic partners (though they might grow and deveplo in other areas), whether it's in an angsty way or a hesistant way. And as for Kakyou, he's so obsessed with Hokuto, ever since she was mentioned in his first appearance, he's only had one scene where he doesn't allude, see, or mention her (yes, I'm love Kakyou so much that I actually counted... -_-; And though Kamui has developed, he's still fixated on Kotori and getting Fuuma back, even if he's not the person he was before.
As for the CLAMP thing... can you think of any major CLAMP characters that have moved on from their "one twoo wuvs"? I can't think of any in Chobits, Card Captor Sakura, X, and Tokyo Babylon, which are the only ones I've read thoroughly.
I could be wrong and missed someone, of course...