PJ---Laurents was nominated for Best Original Screenplay (written directly for the screen). Perhaps his novelized adaptation followed. I KNEW you would pick up on that!
Arthur had a little trick that worked for him on both The Turning Point and The Way We Were.
He would write the screenplay and the novel simultaneously and have his agent (Shirley Bernstein, Lenny's fabulous sister) sell the screenplay to Hollywood, saying several publishing houses were bidding on it and submit the manuscript to publishing houses saying that several studios were bidding on it.
His idea was that Hollywood would be less likely to tamper with his screenplay if they knew the novel was being published as the movie was being made, and that they publisher would be more excited about the novel if they knew a movie was about to come out.