Another WHM chicken little sees the sky falling. The sky is an AST.

[Shurrikhan]

Well, if that's your prerogative, don't let me stop you then. I'm just of opinion it's quite the narrow view of the situation.



AST with Lightspeed will give 2.5s Gravity recasts that are basically front loaded. When extended to 20s via Celestial Opposition, that's essentially 8 GCDs of Gravity so (1,600 potency X #ofTargets)*(AoE Multiplier). One could make the argument that you'd be able to fit a 9th Gravity into the final second of Lightspeed if the AST had a sufficient spell speed value. So, a total of 1,800 potency within 20s via Gravity.

WHM can open a fight with Swiftcast Aero III followed by Assize. This is 590 Potency worth of burst at the beginning by the time we reach the 20s mark (300 + (50 + 40*6) = 590). Then PoM will reduce Holy's cast to 2.4s for 15 seconds. Since you gain the fast cast speed as long as you're beginning to cast before the buff wears out you'll gain 7 GCDs worth of Holy at this cast speed. This is 1,400 potency of Holy + 590 potency of DoT+Assize for a total of 1,990 potency.

Such an MP drain would be a hefty loss for the WHM without also attaching Thin Air, at which point you may as well add Earthen Star into the mix as well...