They don't go "way beyond" though. They have one gimmicky heal that doesn't actually heal that much most of the time. A situation where a BLUe would need to heal 40k-50k HP simply makes it impossible for it to be good at healing. If the party has taken that much damage, the BLU is also missing 40k-50k HP as well, which means WHite Wind is not healing for 40k-50k HP. So unless BLU can magically avoid all raid-wide damage, it isn't going to be healing anything better than a Red Mage or a Paladin. I understanding seeing the big number at cap seems overpowered. But in a real situation, it is useless.