I was getting confused too, so here's the deal (from HP Engineering):
HP Engineering is totally confused as well then, and totally delusional too. Are you sure they knew they were talking to a knowledgeable person? This has all the characteristics of marketing crap.
Think about it:
1. There is no such thing as a spectrometer (or colorimeter) that can see craquelure, and overprint- or drying-artifacts, especially considering they don't allow enough drying time to begin with. And they don't print nearly enough patches to calibrate the Dmax.
2. What constitutes a "linear" response? (Think this one through really long please)
3. True profiling, especially for custom papers, would be profiling the CMYK output, not "colorcorrecting" the RGB input. At the very least it should include adjusting the graybalance.
(Not much use in calibrating the Dmax for primary colors, when combination colors leak off of the page because too much ink was sprayed).
The profiling option on the HP is useful, because it is highly automated and it ensures that the printer will behave consistent. For the average user, this is helpful. For most average printshops this is really helpful. But between "behaving consistent" and "producing a colormatch" there is an insurmountable void that even live humans have not been able to bridge, but oh sure, HP came down the mountain and have blessed humanity with its predictive spirit.
There's definitely room for completely automated color such as implemented in the HPs, especially considering the many printshops that are (still) completely oblivious to cm, and eventually the software will become increasingly smarter and will be able to automate more and more of the profiling process. But Dmax and linearization are not part of that process.