'setads', 'args' and 'go' are not a standard CCS commands. I suspect you're running something other than the CCS that comes bunded with CodeWarrior Dev Studio, which means that the CCS used by the CodeWarrior debugger is different from the ccs that understands 'setads', which could very well explain the different performance results.
Regardless, the 'ccs::set_max_tck' command determines the upper limit of your downloads. The MPC8569 should be able to run at up to 32MHz so try increasing the 'ccs::set_max_tck' value from 12000 to 24000.