First off, what the hell was so difficult about the decision? You're a mediocre (at BEST) linebacker, clearly on the downside. Your friggin' agent probably had to do cartwheels to get his foot in the door, Dhani.
I imagine the conversation went something like this:
Agent: Great news Dhani, I really pulled a rabbit out the hat for you on this one? New Orleans is interested
DJ: But I don't like Cajun food
Agent: STFU asshole, do you have any idea how hard it is to generate interest in a non-impact player like yourself.
DJ: Do they like bow-ties in New Orleans?
Agent: Bow-ties??!! Who gives a fuck about bow-ties, I just got you a paying gig idiot, that's a lot better than trying to pay the rent with that fucking air-guitar routine at the entrance to the subway.
DJ: But I don't like Cajun food....
Agent: Look, there's no way you'll start, but there at least a chance, a small one that this could mean a full season of employment and not just a ploy to learn the Eagles scheme...
DJ: Can you play the Blues with a banjo?
Now the most compelling reason for wanting to hire a dud player like Jones would be, theoretically, said player's familiarity with the schemes run by a tough opponent you expect to face in the coming season. And yes, we play the Saints again this year, in the fucking dome again. So if the Saints feel that they poised for another long playoff run, and they look at the competition within the NFC, one the teams I guarantee they see as a potential roadblock is Philadelphia (just as we see them as such). So you pluck Jones and try to glean clues as to what makes the Philly D tick and how to exploit it.
Here's the problem with the above paragraph: One tried-and-true way to run ball on the Eagles: "Pick on Dhani Jones" is no longer available!! (LOL)
Consider this: When former all-universe RB Marshall Faulk broke down the collapse of the Eagles run defense after the playoff loss to the Saints (this appears on the NFL Network months ago shortly after the game) he called out Dhani Jones' THREE times as misplaying the read and being caught out of position/not making the tackle on the final game-sealing possession.
Given THAT level of understanding of our D, perhaps its to our benefit that Dhani divulge "all he knows" :D