You should not translate for more than two hours at a time. After that, you lose your edge, the language becomes clumsy, rigid.
One of the attractions of translating 'Heroes' is that it's not the kind of play that I write. If it had been, I probably wouldn't have wanted to translate it. There are no one-liners. It's much more a truthful comedy than a play of dazzling wit.
There are certain sorts of jokes which have only to do with the substitution of the unexpected word in a familiar context. If you translated something into French and then had it translated back into English by somebody who didn't know the original, you'd lose what was funny.