It's a nerf to one of the best Tier 1 talent in the game
it's a nerf to the ridiculous shadowbolt spammer dps (combined with the life tap nerf)
it's a slight nerf to the utility of the warlock which in turn makes mages look less bad
it's an attempt to make destro fire a bit more attractive which also boosts the fire mage utility in the raid
Mages utility is laughable. We bring a close to useless buff, a food table that is not even needed and a portal for people who have their hs on cd.
We debuff the bosses with debuffs that are primarily used for our own class. We are dependant on having decent CoE uptime in order to compete against the best dpsers, something which is not often the case as CoR > CoS > CoE.
The CoE uptime would increase if at least one warlock went fire.
Pretty much all the "utility" a mage brings can be replaced by other classes, except for spellsteal on council (yay).
There is currently no reason for any min-maxing guild to bring more than _one_ mage, and probably not even that.
I see this nerf as an attempt to level the field between two very similar classes. Priests just happen to be shot down during the process, which might be justified judging by the utility a priest brings outside their role as a dpser.
Of course these notes may not be true, I'm just showing they can and might be.