If you were to, say, use perl 5.10, would you be able to get rid of some of the parsing (which is likely done in perl) and use named captures with regexes?

$r->route(qr[^/(?<controller>[^/]+)/(?<action>[^/]+)/(?<quality>[^/]+)
+(?:/(?<extras>.*))$])->to(...)
# (ok, an x modifier with some gratuitous whitespace might be wise her
+e..)
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This would give named parameters (through %+ or %-, though I'd likely use %-). And nearly unlimited ability to validate URLs before we get into the real code. For example, being able to send /foo/123 to one piece of code, and /foo/abc to another (based on \d vs \D).

So, if you're given a string, you can have the : markers as above. But if you're given a Regexp reference and the current perl is 5.10, you have the opportunity for some much more interesting handling, which you almost don't even have to handle.