If Dark Knight was good..

[PyurBlue]

TBN is not mitigation, it is a shield.

Which is fine. It absorbs damage, like mitigation does. It also has the advantage of being able to block status effects because it's a shield and it's nice to use as a buffer for HP based healing like Essential Dignity because it allows the tank to remain low on HP without taking damage so that a good tank/healer combo can more easily maximize HP dependent healing gains.

YOu can use 2-3 TBN per trash pull, which equals to 75% health , compare that to Bloodwhetting which not only gives you 10% mitigation and heals you for ~300% health on each use.

The problem in this case isn't TBN.