I use H&L and simply step up. Usually after using 80/100 on the wide belt, I use 120/150/180/220 (on the 3mm orbit ROS) sometimes 320 or higher depending on finish. It typically takes little time to change and provides good and fast results (removing scratch and swirl). Obviously there are lots of variables. But 60 to 320 in one step?. I am skeptical that I could get a swirl free finish (no doubt my inferior equipment) but more power to you!
"the mechanic that would perfect his work must first sharpen his tools.” Confucius