Necroing this post.
I also wonder why ppl still think WHM is the king of dungeons? The speedrun records are all held by AST as their choosen healer, after the insane buff to Lightspeed no longer lowering the potency of skills the gravitiy + LS combo is insanely good for fast aoe bursts to quickly decimate a group of mobs.
They have some of the highest aoe bursts in the game as of now, specially when combined with a mind potion + cleric stance. (obviously every healer can use that combo but for AST quick use of aoe they get a higher dmg output during the short duration of the buffs)
While Holy still has the best mitigation of dmg through stuns, that is no real concern in a normal expert roulette as most tanks have learned to use their CD's for big pulls. For some the stun from holy spam is more of a downside then benefit as DRK loses their mana given from blood price to be able to keep their aoe's up during the pulls.
https://www.speedrun.com/ffxiv/run/me8eqvqm
Im not a Meta healer anymore as im staying away from most savage content in stormblood, but I always enjoyed WHM for its diverse setup for dungeons. To me WHM in 4.5 is a slow casting healer with nothing going for it other then big numbers on heals and a large number of panic buttons.