The problem is, if another team is afraid the C's are going to match their offer to Davis, then they will not give him an offer sheet. However, if they have something the C's might want, they may then try to convince them to do a sign and trade in order to assure they get the guy they want. And it also helps, because it will help the other team create room for Davis' salary by clearing off the other salary.
For example, if Sacramento was interested in signing Davis as a PF to go along with their youth movement, instead of just signing him to an offer sheet, they could go to the C's, and ask if they would be interested in trading Davis, along with an expiring contract or two for Nocioni. By doing this, the C's get a player who probably has more value playing for them than for the Kings, and the Kings end up saving a ton of money both short-term and long-term. They save money short-term, because instead of adding Davis' contract on top of Nocioni's, they have it (along with someone like Allen or Scal) in place of Nocioni's. And then longterm they save money, because Davis would be making less money than Nocioni, and the other contracts would come off the books next summer, while Nocioni's would have stayed on the books for another couple of year.