50% Haste is the soft cap. That's when your GCD will be equal to 1. And any 2.0 speed nukes will also have a cast time of 1--they cannot get any faster. Nukes slower than that (so, say, Arcane Blast which has a 2.5 cast time) will still benefit some. However, proc buffs like Lightweave Embroidery could easily take you passed the cap.
How much haste you want is dependent on your spec and your other stats. When calculating overall DpS for a fight, it acts as a % multiplier. So the larger your base damage, the better the haste is. It doesn't matter if you are flinging spells every second if they only hit like wet noodles.
And Fire, for instance, requires a good amount of crit. So Haste won't be as important if that value is low.
That said, you won't have passive Haste anywhere near 50%. I'm at 700 haste rating and I have 2pc T10. That's 21%.
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IDrownFish wrote:
Anyways, you all are horrible, @#%^ed up people
lolgaxe wrote:
Never underestimate the healing power of a massive dong.