He may have a weird thing going on because iirc he is weak to genjutsu, which may indicate low Resolve, but it's a weird trick of the universe (or the fact that it's a game) that all the things which depend on Resolve help each other. Resisting Enma's presence, not dying of clone sickness, meditation? The assumption that "you just have to get used to more clones for longer and only that will help" is a more rational one IMO, and it's only Hazō's most overpowered ability, Lists Flowcharts and Character Sheets, which allows him to munchkin like that