help my dps (moonkin)

[Seikusa]

wait for the second pot to have both cds up, when you know that BL will be used at the end of the fight, save your "last" cds. when the kill is less then 2 minutes left when you have your last cds ready, save them to use it for BL. since you will not get Incarnation again until the fight is over.
you should use the second pot with bloodlust if your raid lead wont use it at the start. if your CA is less then 30 seconds left when BL starts, it will be up in the BL phase so use your pot at 20s left of BL buff to have it ready for the CA inside BL.

[bl00mie]

FWIW, you should suggest to your raid leader that he's doing your guild a disservice by lusting at the end on a non-burn-phase fight like gruul.

Your entire raid's effective dps will go up a lot by lining it up with 100% of trinkets and cooldowns for everyone in the raid. Fights will be shorter which also increases proc/cooldown uptimes percentages. If the boss enrages enough to matter at low health, lust at the end is warrnted. But there's absolutely no reason to not lust on the pull on gruul.