About all I can gather from this article is that the NT base had built up hacks/workarounds over the years and needed to be cleaned out. The "modularization" stuff sounds like they've made some internal, informal interfaces into real (but still internal) APIs.
Allchin has done this type of thing in the past. Back in the Cairo shell days (1994?), a lowly coder-bee sent him email saying that the effort was too big, too complex, and would never work in practice. The coder-bee suggested that they take the Win95 shell and modify it for the NT base. Allchin replied that he had never heard anything about the problems and called in his subordinates to answer the questions raised. Cairo was cancelled and the Win95 shell was adapted for WinNT (version 3.5?).
I thought this article came out like a month ago. anyway, I have been using the PDC ulitmate winvista 5219 version or what ever it is called. I dont see anything wrong with it. Works just as well as winxp. I have had it hang on install of a few of my PCs.