>I'm now 100 percent satisfied that there is a problem.
If you're convinced, then by all means proceed to have it fixed. I hope it is successful.
But here's what I'm getting at - if you are trying to convince people here there is a problem, or want practical advice on what to do about it, you need to give us some better material to work with
>P.S. in review mode and in Nikon software the focus point can >be seen, so it is in fact possible to determine what the >camera thinks it is focusing on in the absence of a flat >target.
The problem there is that the actual AF sensors do not match up exactly with the displayed focus brackets - in particular, the AF sensor is typically larger than the markings. With an angled target, there will be detail at different distances under the same sensor, which leads to unpredictable results. A flat, parallel target eliminates this variable.