Wolf Kanno is right. The "beat your own party up" tactic still works, but levelling up using "fake commands" doesn't (Eg: casting Esuna and cancelling it repeatedly to level it up). However, spells and weapon levels have an experience bar instead of a percent, and the amount of uses needed to level up a spell/weapon skill is much less than what it takes in the NES/PS version. I think it takes around 5 or 6 uses to level up a spell from level 1 to 2 targetting Rank 1 enemies. So basically, they removed the cheating method of levelling up spells and weapons, but you don't even need it anymore.