Hello Paul,
It's been a while, but I am hoping you return to this thread, as I think you have really hit on something very useful for me.
Perhaps you can clarify a couple of points for us:
1. How can your thumb perform manual focus by not pressing the button? do you mean that your left hand is manual focusing on the lens?

2. What is the advantage of not engaging VR every time you focus? Also, I would assume that VR engages once you touch the shutter?

Thank you,

POC

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