We've been doing our research—i.e., reading the always trustworthy Wikipedia—and we think we've finally figured out what the heck is going on with the Portland Trail Blazers and Darius Miles.
Let's see if we can get this straight now: In 2004, the Blazers gave Miles an ill-advised six-year, $48 million contract. About a year and a half into it, Miles got hurt and had to have microfracture surgery. (Whatever that is.) He missed half of 2006 and all of the next two seasons. Portland, desperate to rid themselves of his contract, had his injury declared "career-ending," which allowed them to cut Miles and get the remainder of his contract taken off the books for salary cap purposes. (Though they still have to pay him the money, I think.) However, if it turns out that the player's career is not over—and it doesn't look like it is—another team can sign him. If he plays in just 10 games, the salary cap relief for his original team is rescinded.
In Portland's case, that's $18 million they cannot afford, which effectively destroys their salary cap on a player who hasn't suited up for them in three years. They are desperate to not let that happen, but to avoid it means sabotaging any attempt by Miles to make a comeback. They preemptively threatened to sue any team that picked him up, claiming any team that did so would only be doing it to hurt the Trail Blazers and not because they feel Miles has any basketball value—which in Portland's eyes, he clearly doesn't because he's a bum. They brought in doctors to testify to his ineptitude, bad mouthed Miles around the league trying to convince everyone his injury was irreversible, and threw in the lawsuit threats just for kicks. Whatever it takes to keep Miles off of NBA courts.
Of course, Memphis probably wasn't interested in playing Miles to begin with, but as soon as Portland dickishly pointed out that such a move would hurt the Trail Blazers franchise, the Grizzlies probably figured, "Yes, let's do that." Spite is a powerful motivator, as is being able to screw over a rival team with a simple ten-day contract. Miles will be on the Memphis roster for at least three more games, and all he has to do is play in two of them to stick it to his old team big time.