How to Manage Sales People: Activity Based Management vs Results Based Management

There has always been a lot of discussion about which is the best approach to managing sales people, activity based management or results based management. For the record, I'm 100% in the results based management camp. I don't believe there is only one way to get a job done. Activity based management assumes there is only one approach to getting a job done and mandates everyone does it that way. In sales that means telling sales people how many calls to make, how many appointments to set, who to call, when to call, etc.  The activities being managed come from the top and the sales people have little autonomy to manager their own business. The approach is defined and then everyone has to follow it. Activity based management assumes there is only one way to get something done and that everyone needs to be doing it. I call foul on that.