Not even manual focus on the FX 14 mm f/2.8 R, with the clutch? You engage manual focus by sliding the focus ring rearward, which reveals a distance scale that you can read against classic DOF markings for different apertures. I have this lens, and just tried turning the focus ring with the lens not mounted on the camera. Looking into the rear of the lens, I see something shifting in re the aperture stop as seen through the glass. Not sure but I think this lens design might be a dozen years old. Sliding the focus ring forward disables it and makes the lens autofocus.
I'm not disagreeing, I'm just curious. I have wondered what's going on in there.