I tried to explain this before in another thread, but I explain my thoughts on Sheild Spec vs. Focused Rage.
Focused Rage - Cuts the cost of rage on all abilities.
Shield Specialization - Gives you rage.
If you dodge a few times in a row, one will slow down your rage loss, while the other will compensate with more rage. It's a preference thing mainly, but imo, Sheild spec will likely get you out of a rage starvation issue faster assuming high avoidance/block levels. Like I said though, mostly preference.
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