They banned him until he agreed to a name change. He appealed the ban, and got a response from one one of the GMs that amounted to little more than, "Sorry. Sucks to be you."
The GM explained that while, yes, the word has a perfectly harmless dictionary definition, they had to appeal to people reading it in a more common and unfortunate way.
I think he got banned because the GMs got tired of fielding tickets and reports by Tumblr crowd. "OMG TRIGGER. HIS NAME IS A TRIGGER! NOW I NEED TO GO SEE MY THERA... AHHH! TRIGGERED AGAIN!"
I find it interesting that the GM drew a parallel with the word "Bitch" - though he carefully danced around the actual word in his letter.
While "it" means "female dog" and in the dictionary sense is perfectly harmless, because of its common view, we have to take it as a negative word.
I can totally see their point here - there is a question of proper decorum in a game. Could you imagine the fainting and scandal, for instance, if the War Chief was to turn to the leader of the Foresaken and say, "Watch your clever mouth, bitch!" I mean, imagine him saying it, and carefully enunciating the final word as if he did not want anyone to miss it. It would be awful if something like that sneaked into the game.
So I guess the name "Therapy" would be banned to for being too, uh, apy.