"Um, well—it's a big construction project." The admission was distinctly sheepish. "Celestia and Luna were determined to deal with all the emergency stuff themselves, out of guilt, I think. At first I thought they were trying to protect me or something, but they said they wanted me to be more free to deal with anything else that came up—things like you showing up, I guess. So I decided to follow up an idea that would keep me busy, and be a benefit to Equestria, but wouldn't tie me down completely."