So you've started reading the description of a trope, but instead of trying to tell you what the trope is about, it starts out describing a scenario, often written either in the second person, or in the third person referring to Alice and Bob.
This description may take a while to set up and execute, even a few paragraphs, but very soon you realize it's a hypothetical situation in which the trope is occurring. It concludes with a Title Drop before proceeding with a straight description, and by now you realize: You've just read an Example as a Thesis.
Example as a Thesis occurs when a trope is described by giving a generic example of it, to help give tropers a better understanding of what the trope is about. Sometimes this works better than a direct thesis, especially if the trope is a complicated scenario that is not easy to find words for. But this has its own risks, too, as the trope may not necessarily be limited to just the example given as a thesis.