Quote Originally Posted by itsokimbatman View Post
Either they're fine and I can throw a regen on them then holy spam to my hearts content, or they get half their health knocked off before my current cast completes, and I struggle to keep them up.
Usual first thing I say in these kind of situations is check gear -- both your own, and your tanks. But if you're encountering the former situation, my first thought is the problem isn't you. This can particularly be a problem levelling SCH, since it doesn't have a cure 2/benefic 2 it can just sit there and spam.

Anyways, it's probably gear (pre 50 tanks can even wear DPS gear), perhaps combined with an uncaring attitude towards CDs. If you want to examine more carefully the reasons behind deaths, you can upload logs to FFlogs, and examine the healing and incoming damage leading up to a death. What CDs were used, if any, etc. Although I believe they only support max level dungeons.