darkglow embroidery or a +80 intellect profession for a disc?
I currently try to determine if I should drop tailoring (which I also have on a main) in favor of inscription [for account utility reasons, not the char. But I'd also like to see if the char benefits anyway]. I don't like the intellect embroidery for healing due to the randomness so it's a dilemma between the mana embroidery and +80 intellect of another profession.
i'd go inscrip simply because MOP shoulder enchants will come from inscription. 2 tailors is redundant. it's not like having an elixir alch and an xmute alch, it's just worthless really. JC would actually be better imo than a 2nd tailor...
straight intellect is better for disc since it affects the strength of your shields (and everything else) versus on proc intellect, since you may or not be shielding at the time of the proc, and darkglow isn't really necessary as disc since the spec doesn't usually have mana problems, especially this late in the expansion.
Also everyone could be at full health when the 480 intellect procs, so ya.
Engineering might be decent if you used the glove enchant right before you start to shield, need burst healing, right before you hymn, or right before the shaman drops mana tide.
Hrm, engineering hah? You actually make a good point. I was thinking about that. The main reason engineering is not very much in my mind is that it's largely - by official design - a "selfish" profession nowadays; it doesn't give much to others so having it on an alt is not that spectacular.
The proc is never wasted, because the Tank is never at full health for 15 seconds.
It's never wasted but it's sometimes very suboptimal to the point of being very, very weak. For example if you need to heal spikes of damage such as in Hagara it might be very unreliable. If you go a few minutes later to Ultraxion it is very optimal, especially for a disc priest since it shields all the time. Nothing is wasted there.
i.e. Only in a minority of fights - that are almost never the final/hardest fights - such utilities work nicely. A healer though can use the mana more reliably even if it could use more intellect. But if that intellect is random it might be best to be getting mana back rather than a random chance to heal more.
Of course such things depend on the amount of intellect or mana given by specific utilities but those are never very imbalanced for the same expansion so the situation stands as described.
Almost unrelated/off topic here, but I was thinking of arcane mage that it may benefit from mana-back utilities though that's usually not the case not because it's very weak but because such specs usually never stop dpsing, so even random intellect may help the overall. However, a healer is rarely "mashing" to get "max HPS" so it's not the same. While one could argue they never stop casting, they also may cast something very weak such as 'Heal' which is not the same as a DPS that will rarely use the weakest spells. At the very least they will only not spend cooldowns.
As compared to a static +80 intellect profession, from tailoring you get:
-80 intellect from lost profession bonuses
-50 intellect from the static intellect back enchant
+580 intellect or spirit with a 50 second ICD and 15 second duration, or about a 25-30% uptime, averaging to 145 to 174 extra intellect or spirit
So tailoring is worth an average of 15 to 44 more intellect than a profession that gives 80 intellect, plus it allows you to opt for spirit instead of intellect. But it has the drawback that some portion of the extra intellect will go to waste.
I think the difference between tailoring and an 80 int profession is marginal. On a challenging encounter your group will rarely be topped off and you'll rarely be at 100% mana, so you should get decent use out of either cloak enchant. Any relative difference between tailoring and another profession is probably outweighed by the cost and hassle of leveling a new profession.
As for lightweave vs. darkglow, I'd recommend lightweave unless you're doing PvP healing or undergeared PvE healing.