Just an observation for those who seek D-max.
Another quote from Todd and Zakia:
In connection with the development of the ASA negative speed method, an experiment was done to determine the print characteristics for the images preferred by the panel of observers. In general, it was found that only a part of the paper curve was used in making excellent prints. Specifically, almost no preferred print contained the maximum density of which the paper was capable. The darkest shadow was quite uniformly found at a point on the D log E curve well below the maximum....