Yes, Capaldi's an old school fan, and he's been watching the show for a lot longer than I have, but he's WRONG! :p

I started watching the show in the Fourth Doctor era when they had finally figured things out and it was always just "the Doctor" in the scripts and in interviews, even though the credits still said Doctor Who, and they were obviously much more enlightened and correct by then even though they still hadn't quite decided how to pronounce "Gallifrey." Therefore calling the character "Doctor Who" is incorrect. QED.

; )