I wonder the usefullness of nested projects. Perhaps folks have other ideas, but so far I see only these reasons:
 A top-level "Project" that only houses other Projects, so CPS "Groups" can be used between projects.
 A top-level "Project" that only houses other Projects, so inter-project "Links" are supported when the top level project is Archived.
I don't see how a construct of one full project (with folders and modules and links) would be inside some other full project. Is there a real-world example of one project being both independant and also subordinate to some other project?