Why is an average wep simming better than a BiS?

Hiya, first post here, just a quick question.

Simming a Blood DK, my Corruption Bone Headlopper @ 460 with haste corruption sims better in m+ than my Geti’ikku @ 445. What I wanted to ask is if the special effect of the weapon (66k heal if a bled enemy is killed) is actually simulated?
The reason Geti’ikku is one of the BiS weapons (at least for blood dk) is because of this effect and how damn much it can heal you, yet in the healing report I’m not seeing anything credited to it.

Thanks in advance!

It is being simulated, here’s an example:
The heal is called Death’s Reward.

The heal is not of very much value for toughness – it only triggers if the target is bleeding when they die, and the bleed is only 1 rppm (modified by haste), so it will only trigger 1-1.5 times per minute or so, and that has to happen to be within 12 sec of when the target is going to die, and on the target that is going to die if you are fighting multiple enemies.

Given that the bleed replaces secondary stats on the item as well… it’s not a very good toughness trade-off at all.

I would assume it’s popular because direct damage item effects are one of the better ways to increase tank DPS.

Thanks very much for the reply, that clears things up for me.