Why do tanks need Determination stat still when they have Tenacity?

[Snarky_Sunseeker]

...why should tanks sacrifice that 5-11% damage reduction that also increases DPS by 5-11%(Tenacity) for a flat 7-12% DPS increase(Determination)?

Why not both? I don't see how the two are mutually exclusive, so I meld Determination and Tenacity. Still, what works for me may not necessarily work for you or someone else, so go with what's optimal for your play style.