When debugging an application someone else has written, generally I'll be given a problem - and I want to find out all the code behind whatever is broken or needs looked into. So you start from a URL, go to your centralised dispatcher router whether that be your Zend bootstrapper, a mod_rewrite rule in a .htaccess file, your django URLs file or.. whatever. From there you'll be able to work out which controller and action you need to look at. In this case I'm looking through a whole bunch of controllers and then their doccomments to see which route matches. Not pleasant.
As someone said, this is pretty clever, but I'm not convinced it leads to maintainable code. Which is the entire point of frameworks and the MVC pattern. There are other ways to implement DRY in a dispatcher without resorting to inlining a pattern into a comment. For example, you could delegate a base pattern to another URLs conf like you do in django.. or use nested routes like the Perl Mojolicious framework:
http://search.cpan.org/~sri/Mojo-0.9/lib/Mojo/Manual/Mojolic...