My AST is so weak, why?

[technole]

i have not yet heal in Dusk Vigil
but i do found healing Paladin and warrior more comfortable than healing Dark-knight
i dont play deep in tank role, only level those 3 tank to around 40, do feel dark-knight slightly more "paper" then other 2

There really isn't anything materially different healing DRK, we have comparable cool downs to PLD that can be up for almost every pull. The job has a higher skill ceiling than PLD and that it's main mechanic is managing MP along with cool downs and skills that can be used for mitigation, threat, and DPS. Anyone who is greatly familiar with tanking before is going to have an easier time with the job, compared to a fresh tank that just got their "first" tank job in HW. The latter I think we are seeing a lot more of nowadays, subpar tanks leveling that also have zilch in cross-class skills from GLD/MRDs so missing the two minor cooldowns like Convalenence and Bloodbath which help healers, so not having those can be an annoyance. Then there is the more common gear issue, not even seeing i120+ when they get to Dusk Vigil like they just came straight off of their AF level 50 quest gear, so yeah. Those two stand out to me as I'm leveling my dps jobs.

Synastry is one of the reason why i mostly play AST now instead of SCH. My gawd its so awesome healing two people at the sametime

You can do that easy on SCH with embrace focus macros.