The only characters with repeated models should be the NPCs. I don't know why the wiki article on the chara.one says that the contained data is only models. For me, when the referenced model is a main character, the data is just animation data. If that wasn't what you meant, well, the PS1 version of FF7 repeated its non-mains all over the place too. I think I heard it's to save CD-ROM seek time.