The bigger the gravestone the higher the rank Doctor Who. I wonder if that's why Clara Oswin Oswald said... "It's smaller on the outside"...because she had already seen it like this. The inside didn't get smaller to fit inside, the outside got bigger.
"I said he was me. I never said he was the Doctor. The name I chose is the Doctor. The name you choose is like a promise you make…he’s the one who broke the promise. He is my secret." And still, Doctor, because he is you, I love him.