I wouldn't scrap your controller just yet. There is nothing wrong with it. I know you said you checked, double checked, and neighbor checked the controller...but..what exactly did you check? For more than one start time? The Greenskeeper controllers also have functions for Programs A,B,C. These might also have start times programmed that are causing multiple cycles. Did you try unplugging the controller and removing the battery to reset the controller to the default settings? If not, you may want to give that a try too.
Tony Posey
Ridge Run Landscapes