Steven Moffat has explained why John Hurt’s regeneration into Christopher Eccleston in The Day of the Doctor was cut before we could see the Ninth Doctor’s face properly.

Moffat says in the new DWM (#473) the main reason was “Human decency.”

He elaborates: “It was one thing to include [Eccleston] among all the other archive Doctors, as they flew in to save the day – in fact, it would have been disgraceful to have left anyone out – but placing him in that scene might have given the impression he’d actually turned up for filming, which would have been crossing the line.

He adds: “Not taking part in the 50th was a difficult decision for Chris, taken after a lot of thought and with great courtesy, and not respecting his wishes would have been grossly unprofessional and disrespectful to a good man and a great Doctor. Number 9 may not have turned up for the celebrations, but there would have been no party without him.”

Still, we’ve at least got this fan version:

On the subject of regeneration, Moffat details that the reason the 11th Doctor was able to heal River’s wrist despite having no regenerations left was that “he had enough regeneration energy to fix a wrist, but not rebuild a whole body.” He likens the situation to Ten growing his hand back.

Moffat also goes into the subject of whether regeneration is death. The short version: “For me the answer is no. Regeneration is not death: it’s way more frightening than that.”