[thisisnotatest]

I'm an engineer at Google who worked on the query parser code in 2009 and 2010. I can assure you that at no point around then did punctuation like square brackets get used, inside or outside quotation marks. The results changing from results that suited your intent to results that didn't must have been caused by other changes to the ranking algorithm or the Web as a whole over those years that happened to be unlucky for you.

Punctuation is a huge challenge for us. We can't simply index all the punctuation on every web page on the internet -- think of the blowup of our index! Think how much slower our search pipeline would be! But we're working on it. Now we recognize some common punctuation uses cases like @ and #. Compare the search results for mattcutts vs. @mattcutts, or obama vs. #obama. We'll keep working on the other ones. The programming ones hinder us coders a lot too. :-)