Yeah, I dunno, the weakness of the 500 is the same as any dSLR: the focus path is not the same as the image path. It shows in these pix, and the pain he relates in getting them.
That is just a question of adjustments and tolerances. Photographers have worked with cameras with a focus path different of the image path for decades and have managed to get perfectly focussed pictures with them.
For example: I use an Hasselblad H4D. With true focus, I can point at the eye of a model and will be sure that I focus on that eye and not on the other one, or the tip of her nose. It is quick, efficient and simple. There is no need for me to fumble with an electronic image on an LCD. Sure, it needs the camera to be built to tight tolerances, but this is what I paid good money for. Why would I want to replace that quick, efficient and simple system by something else?