Any Viper tried dancing in zak body?

What's so thrilling about training without Magic Guard? You don't die in one hit.

relying on heal to recover your HP is much more dangerous than relying on potions, you can't heal immediatly after you do another skill. It's more limited as to when you can use it and, to train without MG, requires you to be able to use shining ray between hits and heals.