Cleric Stance, Chain Strat and Rouse question.

[Fernosaur]

Cleric/Rouse/Whispering Dawn have to be casted beforehand, they affect the spell at the moment you cast them not afterwards.

As for Chain i haven't tested it thoroughly but it technically is a debuff on the boss so even if it is applied afterwards it should work. I have seen a couple of HC speedrunners casting chain after applying DoTs, so it must work like this or they are not as HC as i thought.

Chain is applied after the DoTs to make it align with the rest of the raid buffs, like Trick Attack, Embolden, etc. Same reason why most raiding RDMs will use Embolden way before they get enough Manas to do their combo burst.

That said, if you're going purely for personal gain, use Chain before your DoTs, particularly before you Bane. I'm not 100% sure, but my assumption is that DoTs will snapshot not having Chain on the target if you use them before.

[TitaniaYaerem]

You'll cast Cleric before your DoTs
As for Chain Strat you will want to delay it since sure it may buff your initial DoTs but its a party wide tool that will hold more benefit when it falls in line with Trick, Embolden, etc etc and lines up when people reach their ramp up time.

Rouse you will want to use before you Whispering Dawn or else the Rouse will only effect her Embrace.