A lot of that is going to depend on what products you are using, and is it a da or rotary?
With a da, sure you can get around the door handles. In fact I cant think of any place on the car where a da would not be safe. Whereas with a rotary, you need to be careful about catching an edge and product flashing in heavier worked areas. With both you need to worry about the abrasives in the polish not being worked in all the way on harder to reach areas.
Some people here tape everything, some people tape nothing. It comes down to preference and knowing your products as well as experience and laziness. If your sloppy and sling product everywhere anything can get into crevices or stain.
Since I use a da and Optimum polishes pretty exclusively (which don't stain), the only things I tape are the windshield sprayers, antenna, and the runners on the roof, because those areas easily trap product. The only things I polish by hand is the door jambs, ground effects, A pillars, and around the license plate on the trunk. If i needed to, I would hand polish under the door handles, but I am not careless enough that I would scratch them in the first place.
