I was listening to the audio file of Paolini's presentation at the 2004 Maui Writer's Conference in which he details the self-publishing process of Eragon as well as mentions the "20 or 30" other stories he's already got outlined once the Inheritance Trilogy is completed.
Right, so, based off his own words, the Eragon process took about three years from start to edit to publication, and an additional year of in-house performances prior to Knopf's subsequent offer. Suspending that whole "if this book didn't start to make a turnaround soon, we'd all have to get real jobs" bit of his presentation, say they managed to sell enough to maintain a decent standard of living so that they could continue pushing the book. With no contract and no schedule and no substantial income coming in, I'm just wondering how and when Paolini could sit down and write the next two. I mean, would the trilogy have been his life's work? Would he have even finished it, or abandoned it for a new project? Would he ever have the chance to work on those 20 or 30 other ideas? (For my part, I do hope he hasn't already plotted out everything he'll write in his lifetime; there's no real discovery or growth in picking up an outline from five to ten years ago and filling it in as such.)
It's already been said that, had his parents not more or less "bet the family fortune" on the venture, he might have given up. That in itself could be another topic--his lack of dedication to his own work seems to imply he was too young to be doing this and/or he wasn't passionate about his story to be doing it in the first place. But my main point was the hypothetical curisoity of how Eragon would have panned out without major publication.
(As a side note, how lame is it that I have to fight the urge to cite my sources and add footnotes to a livejournal entry? School totally eats my spontaneity.)