Graff's thesis is that the "non intellectual" things that intensely interest many students actually require more analysis and reflection than standard academic topics. In this sense, these people who identify as "street smart" are engaging in intellectual activities without even knowing it. For example, he discusses the experience of an academic who writes of his upbringing in the Pentecostal church, and the intense textual arguments his parents would have over Bible passages. From his own life, Graff talks about his alienation from books in high school, and how his love of sports, which required analytical skills and sustained attention, made him into a kind of "closet nerd" or "hidden intellectual."

Graff argues that tapping into this hidden intellectualism can be key for getting students more involved in school. This involves awakening in students a kind of intentionality. Graff discusses sharing with high school students an article in which he describes his own anti intellectualism in high school, and how, by engaging in arguments against his "hidden intellectual" theme, the students actually embody in their writing the analytic and close reading skills needed to read any text. While this kind of "gotcha" moment is not always successful in getting students to begin to analyze literary texts, Graff says that such moments are part of a process in making students more self aware of their own intellectual abilities.

I'm not familiar with the Graff quote you mention in your question, but I would say that Graff's use of examples is a kind of "repeating with difference," in that each example makes his point more accessible (less scholarly) while also exploring different ways of thinking about his topic.