The translation circuit is there for viewers not characters. If the story requires a companion to converse with an alien, then the circuit is the short-cut for having to explain to pedants how you can travel through the universe and everyone speaks English. It probably wasn't even thought of until sometime in 1998 when a Usenet post irritatingly asked that very question.
RTD only had to explain the point about the Judoon because he was thinking on his feet after several fans snickeringly pointed out that we heard their language. His real explanation (one Moffatt would be more willing to give) was "Isn't it more interesting and more fun when you get to hear an alien language occasionally? But wouldn't it be tedious if all the dialogue had to go through the Doctor to translate? Then we'd have to explain to you people that the Doctor somehow managed to learn every language in the universe! And the companion would never, ever be able to wander off alone!".
When the story requires that the companion can't understand - for example to convey the disorientation of Clara on her first visit beyond Earth, or because an important plot point requires that a companion either doesn't understand or is disliked by the Tardis - then it doesn't work.
It's possible it's a mark of the Tardis's dislike, but that was conveyed perfectly with the locked door. So it's more likely it was for artistic reasons of having Clara out of her depth on an alien world. After all, she talked to the little girl perfectly well, because that relationship needed it artistically.
Simple.