Bone Harvest

I am curious with the new Blood Knight set why none of the builds using the set seem to use Bone Harvest. I have not used it much as a skill before but it seems like it would be really powerful with the full Blood Knight bonuses. Has anyone tried it and what are your thoughts?

http://www.grimdawn.com/forums/showthread.php?t=72608

Bone Harvest is more of a caster skill, while the Blood Knight set is more of a fighter set (fighter means someone that uses his own hands to smash their enemies, for example Cadence user or FS user or eventually dual wield character that uses procs).

http://www.grimdawn.com/forums/showthread.php?t=72693

80-130k dmg. with Bone Harvest and 100% vitality damage
2.6sec. cooldown, double BH (Time Dilation)

http://www.grimdawn.com/forums/showthread.php?t=72764
http://www.grimdawn.com/forums/showthread.php?t=72746