You don't have to be at the highest level of competition for something to be OP.
And even if they are changing it, that's not relevant to OP's question about warriors being OP at the BEGINNING of expansions.
I apologize to everyone for using "OP" to abbreviate two different things in one post.
---------- Post added 2012-11-25 at 04:59 PM ----------
Because making numbers bigger and smaller is easier than finding ways to balance actual mechanics, unfortunately.