Basically ttg is a kids show and 11 minutes. Since CN makes them fulfill a certain amount of hours (like when they renew a show they give them hours not episodes. So 4 eps is an hour and times six is 6 hours or 24 episodes) the creators often work at a fast pace. Usually they say that even if animation takes nine months, they work on multiple at a time (like for instance transformers prime the writers did 5 episodes at the same time and the episodes get made in ten months each) as not all of the writers work on the same episodes, although they do sit down and all suggest ideas. Su works at a fast pace as according to Lauren zake, when we first watched peridot come onscreen in warp tour, they were already drawing the storyboard for log date.
Plus a lot of CN shows are done by the same people and so they use sim techniques to write episodes. For example they write the episode as a storyboard and make a script that is basically what coincides with each panel so the cast knows what to read. Su and at do the same thing, as does other shows like sponge bob, Sanjay and Craig (basically an outline that gets converted to a storyboard) which is why 11 minute cartoons can cram out 52+ episodes in only about a year. For SpongeBob they said that making a storyboard script is easy, as they might start it around 12 with maybe a break or two and end at like four. And the way it is storyboarded, each of the writers write a scene each for the episode and it gets done twice as quick.
Plus a lot of these shows all record together (the cast for the episode, I mean) instead of seperate, so they can easily accomplish the voices for an episode in about two to three hours.