McBride concludes that we should oppose proposed new fuel-efficiency standards. Why? Because the new standards would discourage manufacturing full-size cars. And if a subcompact car crashes with a full-size car, the subcompact car's passengers are more likely to be seriously injured compared to if two full-size cars crashed. McBride's argument rests on the idea that by discouraging full-size car manufacture, the new standards will decrease safety.

Leggett concludes that we should support the new fuel-efficiency standards. Why? Because the new standards would discourage manufacturing full-size cars. And a car crash involving no full-size cars is much likely to cause a serious injury compared to a car crash involving a full-size car. Leggett's argument rests on the idea that by discouraging full-size car manufacture, the new standards will increase safety.

There are a couple of things McBride and Leggett disagree on. First, they come to opposite conclusions: McBride opposes the new standards, and Leggett supports them. But because both speakers agree that the new standards discourage full-size car manufacture, this indicates another disagreement: McBride thinks we shouldn't discourage full-size car manufacture, and Leggett thinks we should. And finally, their reasons for this reveal a third disagreement: McBride thinks full-size cars increase safety, and Leggett thinks they decrease safety.

At their root, the reason for all these disagreements is that McBride and Leggett take different approaches to road safety. McBride is concerned with the safety of individuals who happen to be in a car crash with at least one full-size car involved. Leggett, on the other hand, considers the possibility of car crashes involving no full-size cars at all. This is where their disagreements stem from.