This amazing 1,000-page book by David Foster Wallace crosses many themes surrounding a gapful plot. There are many theories on the Web about what "really" happens within the narrative breaks that are constant and ultimately leave us to confabulate important pieces of the story.
Two points that I haven't seen elsewhere which I believe are very important:
1. The ordinariness of the extraordinary - Hal Incandenza's communication problem.
The first chapter is in the ending of the chronology and is a kind of fuel towards reading the whole book. What the fuck happened to Hal that he can't communicate anymore? Two mainstream theories blame the mold he ate as a kid and/or the DMZ brainfucking-drug. They are plausible theories and the facts that point to them are indeed interesting. See for instance this.
However, one thing that came to mind is on page 966. It stroke me as a blast when I read it, and it was for me the final answer: I loved the simplicity:
"Hal before a match usually had a wide-eyed ingenuish anxiety of someone who's never been in a situation even remotely like this before."
Hal gets nervous in social situations where something is expected of him. He fears his brother's and mother's opinion. He is weird when the people are watching him play against Stice and before the Gala which is an important event. Finally the College admission, where Uncle Tavis and DeLint and everybody else is expecting success from him.
Simply as that: Hal is a shy guy and unprepared for the exterior world, having been alienated at E.T.A. since age seven.
2. The "romantic" message of the beginning and ending.
DFW was very reader-aware. He must have known that the reader somewhere before the final page stopped and realised that the book was going to end in Gately's digression and "dream" of the death-party of Facklemann. It is a book ending, no matter the plot's structure.
In this part, I realised that this final story was about Gately getting an anti-narcotic shot. A powerful drug that make people lucid. He was goddamn high before this and everything was his mind getting loaded of Dilaudid.
Maybe DFW was saying that the book was a huge trip. Not very different from getting comfortably numb with drugs. It is a kind of drool, though intellectualish. The nobrow atmosphere of the book supports this. Entertainment's function is to entertain, no matter the nature of it. High-art, mass-sports, whatever - the point is to be comfortable with the moment.
The last two paragraphs are about the anti-narcotic kicking in. Gately starts getting lucid, not before seeing a nightmare of drug-addiction and effects of "Party Time". Lucidity brings him to a beach, a bucolic ending and simple as that. No more info.
This is an Epicurean message. Life is about the pursuing of moderate Pleasure. Moderate. People can't be consumed by objects, the way so many characters of IJ are. Even Mario is alienated! (Though less than others...)
Lucidity takes Gately and the reader to a beach, where Gately is simply being.
It's a very sad ending, because we know what will happen to him. He'll become addicted to rehab...
Nevertheless there is a romantic message - of how modern world kills people's souls. We can't be, we need to cling our living to objects.
Related to this and even more sad is what happened to Hal. He developed this romantic individuality.
"I am not just a boy who plays tennis. I have an intrincate history. Experiences and feelings. I'm complex." (p. 11)
Nobody in the room understands him. They represent society. Society crushes individuality. It wants robots, "Fourier Transforms of postures and little routines" (p. 966).
So, the beginning of the book is a pessimistic view of romanticism and the ending an optimistic one. What are the consequences of this upward message residing in the last sentence?