The mystery deepens. Although VR is behaving much better since the cold-boot, there is still an intermittent fault:
Immediately I switch the camera ON with the VR lens fitted, either
a. It operates normally, or
b. VR operates for about 1 second after switching the camera ON, independent of whether the VR switch is ON or OFF (the image in the viewfinder twitches briefly). * If I touch the shutter during that period, VR will subsequently operate normally. * If I leave the shutter during that period, VR will not operate subsequently, but I can restore VR operation by cycling the VR switch.
Has anyone had a similar experience? Is it something I am doing wrong, or is it a known fault?
Meanwhile I have been using my 70-300mm VR lens recently in difficult circumstances, and am really getting to like it used with the D700's amazing 3D autofocus mode.