I apologize for the misleading title; there is no advice for playing Sage that I can offer here. But I did manage to finally limp across the level 90 line on this, my final Healing class, so yay! Some random observations from along the way:
- I really can't play healers in all-unknowns parties unless its like, the MSQ roulette.
- Sage is the Gunbreaker of healers in that I have a rocking time for 95% of a fight and then all of a sudden everything is going pear-shaped, the pear-shape is getting smushed against the wall and all of my buttons are darkened out
- WHM's firehose of green numbers is still the only one that comes close to dampening the anxiety of healing for me
Doesn't mean I won't be getting the gear for Sage, and I most likely will bust it out for some no-stakes play with friends in the future
and that only leaves 20 levels of Reaper to go in the whole FFXIV leveling endeavor

