Because that's how most WARs have been running content.
That being said, I did say that a WAR in the same gear is about equal at MTing to DRK, not any significantly better or worse. As long as WARs maintain their 20-25% max HP over a DRK, then they are roughly the same mitigation-wise. However, as soon as WARs start stance dancing or lowering their HP to the same level as a DRK, the mitigation advantage goes to DRK in MTing.
