Upload & Sell: On
What is the point of this switch on the body and lens? Can't you just leave it in AF, and then move the ring manually when you want to focus manually?
You can do this with a lens that has a "real time manual focus" AF motor, but not with lenses with other types of AF, where you can end up fighting against the AF motor. Additionally, with some cameras, you might always have AF associated with the shutter button. Imagine how torqued you'd be if you carefully used manual focus to place critical focus exactly where you want it, and then the camera moves it to a different place when you push the shutter button.