Elton Brand to sign with Clippers for 13.5mil/year

can someone fill me in why Clippers cant offer Brand more money? I thought they have Brand's right and that allow them to offer him more money even they are over the cap. why Warrior can offer Brand 20 mil more?

 

I think it is because they are under the cap. They are offering big dollars to Baron Davis, to get them right up to the salary cap. But, Brand as a free agent actually occupies more salary cap space right now than he would if signed (something like 150% of his salary). So, they need to sign him first (or renounce him) and then sign Davis with the remaining space. If they give Brand more money without shedding salary on the roster, they'd have to give Davis less.