You know what? I concede that it is not mandatory for healers to DPS. As long as we complete the duty, we are good to go. When I queue up on my DPS class, I won't expect the healer to do more than what is necessary. Furthermore, I'll put up Bio, maybe a Miasma, then let Titan Egi do the rest while I watch Attack on Titan (great anime, btw) on my other monitor. I'll dodge AoEs with my peripheral vision. It isn't mandatory that we clear the dungeon any faster than the 90 minutes allotted, so I'll take my time and do the minimum necessary.