John:
Try to keep this in mind-- Tom Doak's own personal view as espoused at that time in "Confidential Guide" was not enthusiastic about courses in the desert and his overall rating numbers, I believe, bore that out. Nothing wrong with having personal preferences -- but my take on what Doak believed at that time was not exactly glowing about desert locales. Clearly, his opinions could have evolved or changed since the book's publication
Also, the desert area, as home to many recent additions to the golfing market is not as fully MATURED as the other locations that often get far more attention on this site --e.g. the Northeast corridor of the USA, comes quickly to mind. The original concept of target golf -- the "either or" variety have since gone through an evolution in which far superior courses have come forward -- a number of which are often rarely played by the folks on this site. One cannot downplay "homerism" as a reflection of what certain people really see as quality golf locations.
Personally, given the fact that I have sampled nearly all of the key courses in the desert SW of America I can say that there are a few courses, I believe, are at the 9 level now. I am a mega fan of Black Mesa, as many are aware, and see the work Baxter Spann did there, in concert with Eddie Peck and Pat Brockwell, in comparable terms to the reviews people bring forward about Pacific Dunes. Although the two courses are worlds apart in terms of styles / locations -- the essence of what Black Mesa provides in its rich array of design ingredients is no less, in my mind, to what you hear about when people rave about Pac Dunes.
I've also said many times that far too often on GCA, there's a tendency for people to apply higher rating numbers because of the person who's done the work -- even if people downplay that last statement -- I do seeing it have some effect on the final outcome / disposition of what people believe.
Let me also point out that the work of Phil Mickelson and Gary Stephenson at the original 18 at Whisper Rock is also superlative stuff IMHO. The course offers a far different version in how a desert environment can be integrated in a manner that's beyond the limited "either or" type courses that have for too long dominated the agenda of so many other courses. Whisper Rock has all the aspects that so many people gush about with other layouts -- there's sufficient width, the challenges can be applied to the top tier players and the greens are richly diverse in terms of shape, contour and demands.
You also mentioned Outlaw at DM -- personally, I don't see the course at the 9 level but I do see it as being a solid 7 because the Nicklaus team offered a completely different version of golf than what you see with their other layouts at DM. Chirichua -- also at DM -- is another "must" play for those coming to the AZ desert. In my mind, I would rate the layout at the 8 level.
John, you can throw into the mix the qualities found at Desert Forest -- a truely classic Red Lawrence design. I'd give it a 9 in my personal assessments of courses played.
You also have to bear in mind that few areas of the USA -- will have an oversupply of 9 and 10 for the very reason that 9 and 10 rated layouts will be in short supply. I don't see the desert locale as working against that possibility but clearly my enthusiasm for the region is not shared by others. Like I said many times before -- some people favor certain types of food -- the desert locale is like Thai food -- if your taste buds are geared towards and steak and potato type foods then Thai food will not be toward you liking.