There is something to keep in mind when talking about "clean" code. Code that operates within a languages strengths in usually more robust, but also more "natural". Sure, you use a regular expression, but Perl isn't really about regular expressions (entirely). Perl is more generally about list processing.

Consider the Schwartzian Transform. This is a powerful took which is the direct product of list oriented thinking. Ovid's solution stems from Perlish thinking. map and grep are list tools, and Ovid combines them into something that is clearly in the languages idiom, and therefore "clean". An anology would be the sentence "Sarcasm is the lowest form of wit I think not".It is grammatically correct, and uses few grammatical concepts. But it is hard to read and understand because it is outside of the languages idiom.

Cheers,
Erik