1) Limit Break's damage has no modifier on what buffs or debuffs you or the boss have. It is calculated by the average ilvl weapons the entire party has equipped. To maximize your use of LB (when able), it is best to have all your dots fresh while you cast it (so you're doing damage while charging LB). Save your CDs/Buffs for AFTER the LB cast.
2) BLMs restore their own mana, they were probably mad there was no BRD for Foes Requiem.
3) I go through coil with a static, because the level of incompetency from the general populace is unbearable.