i will walk 500 miles

“Honestly, I felt that the inclusion was the perfect nod to the Doctor. Those who know him have all immediately recognized his materialization. But to those who don’t know him, it was merely noise and not enough to warrant further thought. (I mean, all the companions come running from blocks away when the TARDIS lands in a city, yet no one else ever takes notice). Plus, The Doctor has never gone out of his way to grab the limelight. He (mostly) just observes. So I think that was Danny’s way of letting us, those in the know, know that the Doctor was indeed there, and that if he had to step in to stop any threat, then we will never have to know. Because that is the true Doctor, the silent guardian.”