After the first with Anderson Danaher said he didn't like those low kicks that Anderson was landing on The Chris. Danaher is a really good coach also trains GSP he probably left because of a money issue or something.
Danaher also has a reputation for being more than a bit odd. He wore his rash guard to Serra's wedding. It wouldn't surprise me if he somehow got on Chris's nerves or something. People competing at high levels often have very strong personalities, and they don't always mesh.