Silence in the Library (1) - S4-E8
Continuity mistake: When the girl recognizes the Doctor on her TV, telling him that he was in her library, and he reacts, the position of her pencil crayon in her hand changes between shots. (00:20:45)
Silence in the Library (1) - S4-E8
Continuity mistake: After Miss Evangelista is killed, we see her communicator as her "ghost" slowly fades. In one shot we see from a slight distance the lights left lit tick down to 3, then a short while passes, we cut back and the lights are back to 4. They then tick down to 3 again.
Chosen answer: 1) When Stephen Moffat took over he ignored a lot of what had been developed before (there is not in-universe answer). 2) It would have killed Rose, so the Doctor absorbed the energy. His body regenerated before the energy could do a significant amount of damage that would prevent regeneration.