Yeah, a lot of the AoEs in CT bypass buffs (I assume all, but since I've mostly healed all I know for sure are Galvanize and Stoneskin. But the poison from the left path also bypasses every defensive buff, just doing a flat 200 damage every tick, so I assume everything that bypasses SS and Galv also bypasses self-buffs as well)

This does make AoE healing with Succor a real pain if you have 2 SCH...