At least they admit Linux is advantage over windows :)
Well, at least even Blizzard admits Linux is advantage over windows, buahahaha :D. Though I don't see how it's "unfair" granted everyone could download it for free.
A third party program is any file or program that is used in addition to the game to gain an unfair advantage
Linux is not the issue...
This blue post should quell any doubts about players getting banned running Diablo III on Linux, or World of Warcraft even: