Misery is a gain because you put it under raid buffs, if you aren’t using 4 lilys per minute you are losing damage, that is the long and short of it, I don’t know what else to tell you

WHM having more expensive GCD’s (which it’s only more expensive than AST as SCH is equal in cost and SGE in only a fraction cheaper) isn’t really a factor given how rarely GCD’s are used and if they need to be used in a pinch thin air is a larger gain than anything else (except arguably recitation). in a timeline fight where you plan out your MP WHM is strongest because of its lily’s. All healers struggle with recovery as they lack MP unless their resources are coming off CD almost immediately. Whether the other healers use an oGCD or WHM uses a lily isn’t really relevant to the point. I know you are saying “in a recovery situation WHM actually has to cast something the other healers can use oGCD’s” but in that case WHM’s “oGCD” so to speak is a lily, it doesn’t have to cast any more than the others on that front

In pure maths terms WHM has the strongest economy and all healers suck at recovery is basically the long and short of it