This next bit is probably something outside your control, but if you pick up an item that is say 'level 2' or has an enchant on it, when you 'split' it, the item will drop to level 1 and the split item will not have the enchant. The contents will be the same, but every item is now treated as a stack of 2. So chests in the world will say hard iron chest (2). The 2 of any item if 1 seems to make EVERY item, not just ones you pick up, duplicate.
