Recently I saw the old episode where the Doctor meets River in the Library, and she seems almost surprised he doesn't know her, implying that when she first met him, it was his tenth forum she first met. (Why else expect the tenth form to know her, and be surprised when he didn't?) Thing is, we now know that her first contact with the Doctor was in his 11th form. Why would she have expected the 10th to know her, and be surprised he didn't? Also, why does the 11th at a later point say to her almost defiantly "Just who ARE you River Song?" The way the line is delivered, he acts like he has no idea who she is, like he doesn't even remember that SHE KNOWS HIS NAME, and in the 10th Doctor's words "There's only one person I'd have told my name to". So why does the 11th act like she's such an unknown, distant thing? I can see her comment in the library being due to the writers not knowing Tennant would leave before they could do a lot with River, but it does make a mess that should be ironed out. Plus, 11th's comments are just plain strange, since the writers certainly had older episodes to go by in knowing just how familar the Doctor should be with River. Anyone have any ideas, read anything from behind the scenes, etc? Even a little speculation would be welcome, provided it's presented as such. Thanks.