Disclaimer: My favorite Doctor is Tom Baker. This is a work of comedy designed to poke fun at how Steven Moffat writes Doctor Who. Also I hate 10 x Rose with a burning passion.
River Song knew 10’s face. She remarked how he looked “younger”. She also had 10’s blue sonic. Let’s say that this inconsistency wasn’t caused by Silence in the Library being written before Moffat knew Tennant was going to leave the role. Let’s say this was all part of this MASTER PLAN. River recognizes 10, but 10 first met River when she died. The logical conclusion is that, yes - 11 degenerates into 10.