Here are the first 20 terms from the Cultural Literacy list. Imagine yourself in a conversation with a stranger. How many of them would you expect to surface ? Are they even the sort of terms you would expect? If these terms did indeed arise, would the conversation come to a grinding halt if either party were not familiar with them?
Abandon hope, all ye who enter here
Absence makes the heart grow fonder
These bits and pieces might be important to some particular conversations under some particular circumstances, but they are not essential to one's knowledge. In any case, and this is the key point, if you mention the rock group AC/DC to me, I can always ask you who they are or decide to talk to someone else with whom I might have more in common.
Is the lack of familiarity with such terms the stuff from which social decay is made? To say the least, it's questionable whether these are the pieces of knowledge on which national unity and full citizenship are based. Even if they are important for some conversations in some circumstances, the major impact of a list like this is only to build the myth of the Right Answer. Children faced with random pieces of information cannot understand why the knowledge is important (in fact much of it probably is not at all important), but can only come to believe that there is so much that they don't know that all is lost.
Where am I in the content of the book?