As I recall, the writers backed off from the slimy weasel angle pretty quickly in favor of the charming Irishman angle--maybe when they figured out that Mary and Tom had chemistry (unlike the previous guys they'd tried to use as romantic rivals for Jack). The writers did seem to flail around a lot where Tom was concerned, though, especially after Mary and Jack's reunion. Tom had some pretty wacky storylines after that. But I really liked him with Mary...