life leech leaves 3-20 hp unleeched

Hi,
I just ran an underground sea map with no regen, my skill was linked in bringer of rain:
inc area of effect, blood magic, ancestral warchief and added fire damage.

bug number is 3,066,276,489.

screenshot of the situation:


full image link:
http://i.imgur.com/otGnoNh.jpg

no vaal pact, i repeatedly checked that killing monsters with chieftain life leech fills life to ALMOST full life.

it is NOT the situation of life-leech-to-full then monster-hit-for-3 damage.
i'm standing away from melee monsters, totems are hitting them, i am getting no life back when im above FULL_LIFE-20.

it's as if life leech works in ticks that are too large, and it doesn't activate when there's not a larger than X amount of life to be leeched.