I think the reason why the WotLK and Cata legendaries are so wonky and imba is back to tiered progression again. In TBC the legendaries were rewards for the very end content (though sunwell ended up coming out after illidan, but then thor'dal was the end item). You had to work to get up there to even have the chance to get a legendary. When you eliminate tiered progression and make whatever the current patch is the only content that matters, legendaries get way more out of wack than in TBC.
"If the world is something you accept rather than interpret, then you're susceptible to the influence of charismatic idiots." -Neil deGrasee Tyson
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