Marc Spears on the Daily Dime:

Cassell didn't make big money early in his career, so it would be hard to walk away from a contract paying $6,150,000. Also keep in mind, as cheap as the Clippers are, they would try to squeeze as much money as possible out of Cassell especially now that he's their starting point guard looking at an opportunity to make a break for utopia. A source told the Boston Globe that the Clippers would be interested in a buyout if Cassell would give up major money.

So basically it comes to this: what's more important to Cassell, playing for a potential championship or getting paid?

The answer to that question will likely determine whether he will be reunited with Garnett.