As in-depth as I went into how Red Mages cast magic, I couldn't answer an important question:

How do they cast black/white magic without it vaporizing themselves, regardless of how little mana they're actually using? Are they merely employing techniques to generate a similar effect as the prefix "ver-" on their spells would note, or are they performing actual black and white spells? The story doesn't clear up much about this, other than they are doing it, not so much the how or what.