I was looking around on Omnifile and found this excerpt from an interview with Delillo in a book review--
"He has admitted to being strongly influenced by the cinematic techniques of Jean-Luc Godard, and in an interview with Tom LeClair (referred to in LeClair's very interesting book on DeLillo called In the Loop), DeLillo said that the cinematic qualities which influenced his writing were "the strong image, the short ambiguous scene...the artificiality, the arbitrary choices of some directors, the cutting and editing."
The reviewer is convinced that the "arbitrary" component of Delillo's backwards swerves in time is actually the dominant component of the entire scheme, and presently, I'm inclined to side with him. There is some commentary about how the backwards motion through time suggests that such a progression is how history can be best understood, but does a deeper rationale exist? Do you think there are other reasons for breaking the novel up into its respective times and locales?
Your post reminded me of our conversation in class about Underworld and the Great Gatsby. The infamous last line of The Great Gatsby-- "So we beat on, boats against the current, borne back ceaselessly into the past" (Fitzgerald 180)--reminds me so much of the backwards motion in time that you described. I'm not sure if there's a deeper rationale for the backwards progression, but your idea that backwards is how history is best understood certainly is valid. It's interesting that the novel places such an emphasis on history while the style of the novel does, in fact, travel backwards through history. Is this an instance of art imitating "life?"
It's also a natural consequence that as we move further into the past, it becomes continually more relevant to the future. I like to think of this as a cyclical ashes to ashes, dust to dust, so that as we row forward, the ghosts of our past also continue to haunt us more and more until we reconcile with them and thereby ultimately return to our pure forms.
It's odd that he does cut up into scenes of random length and random time period; as with GR, I think it's a reminder of the randomness of the critical periods when people can make small crucial changes that will free them. In Underworld, however, in most of these situations, the characters fail to seize on the opportunity for agency.