"Nolan knows, however, that the natural target of the blockbuster is the lowest common denominator, and he’s had to build into his filmmaking practice personal safeguards against what he calls “chasing an audience.” In preparation for each film, he spends a week or two bashing out a little précis, on the same typewriter his father gave him when he was 21. (It appears as a prop in “Following.”) Often that précis doesn’t even talk much about the plot; it’s supposed to represent the feeling he wants to elicit, the texture of the fable. He keeps it in a file and returns to it from time to time to make sure he hasn’t lost touch with his original idea. He also doesn’t do traditional scored research screenings or focus groups, choosing instead to show his films to a handful of people at a time as he’s editing."

  The Exacting, Expansive Mind of Cristopher Nolan.