"Nikon, while admitting the problem, has never published any statistics"
I haven't seen any admission of an admission by Nikon. Can you post a link to where they have done? It isn't something Nikon UK are talking about!
I have tried 3 D800s and they all had the same left AF issue. The last one got sent to Nikon UK because, while denying they had ever heard of this problem, said they could fix it without issue. The first two came from the same batch and so I thought maybe the problem wasn't as widespread as it appeared. Also Nikon were saying they would sort it out.
First time the camera came back with the Left point fine but all the others messed up so that no amount of AF fine tune would work. When I called they told me that the high resolution of the camera was just showing up issues that were in every AF system. When I asked why some points consistently worked and others didn't they told me to send it back in. Even if this was the case, they were basically admitting that their AF system was not adquate for the D800 sensor.
I did return it and the second time it came back I could get the centre AF point to focus on my 50mm f1.4 with a +16 tuning but as I moved to the left side, the AF got progressively worse again.
I've given up and am sending it back to Amazon.
While I'd love the sensor's capabilities, I don't believe Nikon's AF system is up to the job of the higher resolution involved. I am left slightly anxiously wondering what will happen when my D700s really need to be replaced!
There's an interesting blog by Lloyd Chambers here: