Mefisto

Spirit BarrageManitou deals 6000% damage over 20 seconds. Does the Manitou attack speed buff from Gazing Demise mean that Manitou ultimately deals more than 6000% when Gazing Demise is equipped?

At paragon 669, LoD gem level 68 with 5 ancients I'm getting owned at GR 80 while the typhon hydra build pretty much cruises through GR 95 so far. Am I correct in concluding this build only works with all ancients and a maxed out LoD gem?