Wow. I was almost hesitant to post this SoPW at first, but now I'm glad I did, and more. Even though it wasn't the original intent of the post, I've sped the code up by about 40% (thanks to some back-and-forth with BrowserUk), and that makes me happy. More importantly I've learned several new techniques.

Let me summarize the new things I learned, just for my own sake. :)

• @hash{ somelist } = ();
• m//g in list context
• m//g in scalar context

Man, this is some good stuff. Many thanks all around.