AoE DMG: Depending on the AoE, it can one shot you. In this case, you're potentially wasting MP rebuffing once you raise and the MP you had before raising (Don't raise to full stats). Moreover, if you have SS up, you're wearing out the HP gained (200DMG AoE? Your SS just became 150HP instead of remaining 350). Over time, this will cost you MP as you have to refresh SS more often. More casts = more MP wasted since you wouldn't have to cast as much had you been out of range. Thus, you're spending more MP than a mage standing out of range would.