The article says she was experimenting with her regeneration. I haven't seenany of the old episodes but it's possible that a chemical astro-scientist (made that up) could enter an event that would bi-generate them. Just a thought

I saw this from the first episode and it is definitely the case. I am enjoying the series and the things it seems to be setting up. I actually love the hidden depth of Russell t Davies writing, especially the use of musical theory.