North by Northwest is a 1959 American thriller film directed by Alfred Hitchcock, starring Cary Grant, Eva Marie Saint and James Mason. The screenplay was written by Ernest Lehman. North by Northwest is a tale of mistaken identity, with an innocent man pursued across the United States by agents of a mysterious organization who want to stop his interference in their plans to smuggle out microfilm containing government secrets.
I've always thought this quote describes Rory more than the Doctor. The Doctor likes to mention that good men don't need rules and since the Doctor claims he has rules he is implying that Demons Run refers not to him but to Rory. (Disclaimer: I think the Doctor is a good man but this just seems to make sense especially as this is Rory's first war, not the Doctor's.)