I can assure you it really works, when you get the hang of it you can actually have the focus anywhere you want in the frame. Even wide open. I prefer it often over the AF of my Nikon (have you ever felt none of the AF brackets is at the place where you actually want it??)
To get back at the topic of the thread. I don't know about that. I just work with all sorts of formats and prefer using MF when I can. Sure great quality but most of all I just like working with it. It is already hard work to make a living from photography but can I at least use what I like?
Live view on the D800 lets you focus right upto the instant you shoot, right off the sensor and anywhere in the frame.
While True Focus does have it's merits it has it's limitations too. It requires focus and recompose... that alone can be annoying and distracting for the subject and a real pain when on a tripod.
Also true focus DOES NOT account for any camera movements other than the angle of the lens. It cannot detect if the camera moves forward or backwards. Recomposing hand held with a heavy camera will almost always result in camera movement other than lens angle.
On a tripod unless you have a lens centered panoramic head there will always be some forward or backwards movement due to the point of rotation of the head.
The description of true focus with the catch phrase "absolute position lock" is a bit misleading.
All of this is covered in a white paper by Hasselblad:
For example with the 80mm at 1m from the subject they say this:
When the camera is tilted for composition, the point of maximum
sharpness falls just behind the eyes. However, the DOF
is almost large enough to render the eye sharp making the
difference hard to see. A camera movement closer or further
away from the camera even as small as 1 cm will change the
result and True Focus might not fully correct the focus.
The gist of the article is that True Focus is effective with wider angle lenses and marginal with normal lenses.
With longer than normal lenses it's of little or no help at all.
Totally unusable with tilt shift.
Here is the link to the full article:http://www.hasselbladusa.com/media/2234814/when%20true%20focus%20makes%20a%20difference.pdf
I have shot all formats including beauty campaigns with 8x10 and at wide apertures. I have learned that to keep thing in focus there are all sorts of tricks, with 8x10 for example it is important to pose the model very still and to both focus and shoot at the same point of the models breathing cycle.
Being that I like shooting wide open I was enthusiastic about true focus, but found it was not all it was made out to be by marketing and some of the "fanbase".
I tested it for a good few hours in a row but found it not as effective as I was lead to believe it was.
Very unfortunate because I loved the look of the 100mm 2.2
Obviously the marketing brochures were not written by the same guys at Hasselblad that wrote the article "WHEN TRUE FOCUS MAKES A DIFFERENCE".
I do not shoot much with wide angles, mainly normal to twice normal focal length.
In those ranges I found the GX680 with the moving loup high magnification finder and manual focusing gave me better results with both film and digital.
Same goes for 35mm DSLR with live view or regular focus. With regular focus even composition that are off center still place focus points close enough.
With live view focus no problems at all.