I don't get how oxidative additions "oxidize" the metal. For example, methyl chloride. Lets say the chloride anion donates 2 electrons to form a bond with the metal. The metal gains 2 new electrons so this is a reduction isn't it? The metals oxidation state should increase by 2. The methyl cation will also form a bond using two of the electrons from the metal atoms oxidation state should go down 2 again. I don't see how the metals oxidation state increases by 2.