I know this has probibly been said far to many times, but I'm fairly sure that the odds are stacked against the white mage more than any other class in pvp. With the low hp, blasted casting times and the lack of suplamentery skills it seems like the only way to have a useful white mage is to not have one at all. Even with the cross class skills (swift cast, sure cast, etc) the usefulness of a white mage
is strictly restricted to repose and bait... I say this from my pvp experience as a tank not a healer.