The Family of Blood (2) - S3-E9
Continuity mistake: As the scarecrow-soldiers advance on the school to do battle, the scene cuts to Sister of Mine, looking out from a school window. There is heavy rainfall outside. When we immediately cut back to the advancing scarecrows, it is a cold, clear night. (00:10:00)
The Family of Blood (2) - S3-E9
Continuity mistake: When the Doctor comes back to the Cartwright house after imprisoning the Family, Joan walks over to the window and looks out, clasping her hands in front of her. In the next shot, when she asks the Doctor if it's done, her hands are suddenly by her sides, and she is shown clasping them again. (00:34:45)
The Family of Blood (2) - S3-E9
Continuity mistake: When the Doctor and Martha hug after he thanks her for looking after him, the position of her arms changes between shots. (00:38:20)
The Family of Blood (2) - S3-E9
Continuity mistake: When Martha finishes listing off the bones of the hand to Joan, in order to prove that she's a medical student from the future, in a shot facing Joan, Martha's thumb is extended. In the next shot, facing Martha, her thumb is suddenly folded back, as if she was using her hand to display the number 4. (00:12:15)
The Family of Blood (2) - S3-E9
Continuity mistake: When Sister of Mine enters the school's courtyard after the battle with the scarecrows, her right hand is holding her balloon at the bottom, with the bottom of the string wrapped around her left hand. In the next shot, facing her, her right hand is at her side, with the balloon floating above her left hand. The balloon proceeds to jump between positions until Sister of Mine murders the headmaster. (00:18:00)
The Family of Blood (2) - S3-E9
Continuity mistake: When Timothy opens the watch into the girl's eyes, Jeremy Baines shouts "Time Lord", then a few seconds later; "What are we waiting for. Attack!" There is then a shot looking down on the scarecrows, Jeremy and Jenny. If you look closely at Jeremy Baines, it's a different actor playing him. (00:16:20)
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.