Ooooh, wow. I'll look for the movers then. Too bad you can't find them earlier in the game :/ Far as I know, once you get to the north cave, you can't leave again, right? And if you can't leave, you can't exactly get the master materias, right? I mean, don't you have to, once you master a whole set, go back to bugenhagen or wherever the huge materia are and touch it and then you get it?
(I don't know since I've never once fully mastered any set since I've always gotten tired of leveling up the slow materia)