Now this is very interesting, and I heartliy agree. Because I disagree very much completely with those who claims all JKR says is law. 'tis not. Her books are law. Interviews and such can be used for interpretation, but is not law. Who knows, if Mary had interviewed her, and argued against Harry becoming an auror and for his becoming a life saver instead, maybe they'd agreed. Maybe JKR would've changed her mind, and found Mary to be correct. I think so. But then again, that's my not at all humble opinion.