""You have to remember; regeneration is a plot device created to solve a casting problem. If Doctor Who is popular there's no way they would cancel the show, the BBC wouldn't allow it, they will create a new plot device. The Doctor will go on a quest for the lost crystal of Rassilon which will extend his life" - Steven Moffat, Gallifrey One Convention, 2007, The Eighteenth Ammendment of Gallifrey" - Sean Reiser