Hey Thomas, great to hear from you and thanks so much for joining the Strong Towns Book Club! Chapters one and two discuss the complexity of human habitats and how—through trial and error—our ancestors learned that the most resilient places incrementally adapt and evolve as the needs of the household or the neighborhood as a whole evolved. These McMansions, I imagine, can't adapt.
How are these infill lots zoned? Can a developer build anything besides large single-family homes? If not, I think you'll enjoy this article on dynamic zoning codes10.
The Referenced Materials5 section for chapters one and two also include several links which will help give you the language to advocate for a more adaptable use on infill lots. I've included a few of my favorite links below:
Let me know what you think.