I think loh mechanics changed already.Its the same whether vs 1 target or large amount of mobs.
As long as you do damage, you get that same amount of life as whats on your sheet loh according to your attack speed or the animation of your attacks.

Think of the new loh as life regen, but you need to hit something for it to work.



That being said, loh is for tanky ranged build or melee class.

Sentry proc bleed on crit, can couple with boon of the hoarder if you use it last time I check.