Complexity

Isn't "root" now an ambiguous term? Don't we now have local root and global or system root? We certainly don't want local root to have privileges to do things like open arbitrary files by inode number. For filesystems the local root mounted or owns perhaps, but certainly not with regard to filesystems mounted by system root or other local root users.

Unless the idea is to adopt the convention that "root" always refers to system root, and never to local root without further qualification, any such reference is likely to lead to some considerable degree of confusion. This thread is a perfect example.