I have problems to see a case where my approach doesn't work.

I can't see a case where it wouldn't "work", but I also can't see any typical case in which it would do anything useful.

Assuming an unambiguous file system, if you have a xyzzy.pm file defining a package Foo and its structure/content and a bunch of other namespaces and their contents, the only way to establish the Foo namespace (and all the others) is by a  use xyzzy; statement. Once the  use xyzzy; statement is executed, all the namespaces are established, and xyzzy cannot be use-ed again with any effect because it is present in the  %INC structure. If one then wants to access one of these namespaces, a  packagenamespace; statement will do the trick.

OTOH, if you have a Perl inclusion directory structure with a slew of Foo.pm files in it, any  use Foo; statement is an open invitation to a major brain tumor. Surely, the best approach is to have a clean, unambiguous inclusion path to begin with. If you have some weird monkey patching/phasing/path resolution/??? problem such as haukex alludes to here, patching  %INC in this way may be your only salvation, but again, isn't studious avoidance rather than acceptance the best way to deal with such an unusual (one would hope) situation?