In a recent essay, the author discusses the complexities of social media's impact on modern communication. The text is organized to first acknowledge the benefits of social media, followed by a detailed examination of its shortcomings, ultimately concluding with a call for more mindful usage. The author connects each section not just through thematic progression but also by employing contrasting examples between personal communication and public discourse.

Given this structure, what is the primary rhetorical strategy utilized by the author in developing the argument?