i think he means a balance of MP efficiency to damage or something. But one of the main aspects of the balancing act was to make your stone do closer damage to thunder. so you dont have a stone spell doin 8 dmg while your thunder breaks 200. I never understood why give monsters weaknesses to various elements when using thunder or blizzard almost always did way more damage than using stone when it was the weakness. But now after the change your stone does within 50 damage of thunder so its not so far off base (50 dmg isnt an exact figure just an example number)