Say my Chinese name is one of these unlucky keywords. It'll inadvertently black out some of the coverage of Hong Kong entertainer Leon Lai. Lai's complete name is the same as my first name Liming and my last name, which appears first in Chinese custom, is the same as "week". So, if a web page mentions "This week Leon Lai did this and that", it'll form a keyword. And since you naturally pause after "week" while reading, you will never know what's at fault. (You won't be able to run your article through the list because it's a secret.)
Of course, people often need to use the keywords for innocent reasons. For example, "homosexuality" (tong xing lian) is on Green Dam's blacklist. It simply shows the blatant lack of common sense on the part of the designers. Being gay does not equal gay porn, for God's sake. But never mind. Many magazines have blacklisted the word, too. So I substitute it with the much more colloquial term "tong zhi" (comrade). I can bet all the homophobia in the world that "tong zhi" would never be blocked by Green Dam because that would essentially obliterate the complete history of the Communist Party of China.
So, don't worry about freedom of expression being curtailed by the busy nanny. If anything, it'll force the Chinese language to abandon its clichs and adopt colorful new expressions that lexicographers will never be able to track down and catalogue. For one thing, combined words will be more popular as people use Chinese characters, pinyin and homonyms in combination to avoid the dam. The beauty of these terms is, they don't require a degree in linguistics. They are quite recognizable to us humans but will baffle the hell out of GD algorithms.
See it as a form of classic poetry, which is bound by strict rules of rhyme and rhythm. When language is enslaved, it bursts out in unexpected directions. Parents have been complaining of being unable to decipher what their kids write online. Pretty soon, censors will have a hard time decoding the slang terms, inserted alphabet and bewildering spaces. So their expansion of keywords may grow exponentially, bringing down millions of innocent websites in the process. This goes on until the complete database of Chinese words are used up, by which time Chairman Mao's vision of Romanization will become a reality. (And don't even think of picking on pinyin words. The Chinese language has so many homonyms that blacklisting a few hundred characters may wipe out the language.)
So, don't cry for us inside the Great Firewall. We'll have the best material for black humor.