@ch0si I think we are sure that any face blindness she has is reasonable in nature, since she does recognize Tanaka on the second try in the cafeteria (but can't connect him to a name).
So it might be involved, but it might also just be down to not being good at remembering names and not having learned the helpful tricks.
I remember faces pretty well but it takes me a lot more work to remember names consistently (and when I was in school and didn't know the tricks or put down the effort that much, it'd take me 2-3 years before I had learned all the names in class.)
Hmm.. but yea, thinking it over, she probably does have at least some face blindness (or a similar problem with faces), since she also mentions that they dress too alike (meaning she usually would use clothes style to help distinguish between people - which also has to imply that she somehow went to a school that didn't really use uniforms). But again she's not completely blind, since it is implied that she learns faces after a while (as well as shown that with enough staring she managed to catch some visual cue on Tanaka).