Matt Smith and David Tennant - Is That a Good Idea?

Matt Smith and David Tennant were both in their garb, dressed as the doctors. They just clearly absolutely loved each other's company. And it was weird because David Tennant was saying how he was nervous about coming back. He actually, one interesting thing he said was that to be the doctor, he was rehearsing and he couldn't get it right. So he learned how to be a doctor by studying himself. By watching himself. Brilliant.