Prompt

Reason through the following problem and give your best answer. Think it through carefully: state your assumptions, quantify where you can, weigh the evidence, flag what is uncertain, and end with a concise verdict or recommendation. Aim for a thorough but focused response of roughly 400 to 700 words.

PROBLEM:
A city keeps widening its main highway to fix congestion. Each expansion eases traffic for a year or two, then congestion returns worse than before, and leadership blames population growth. Diagnose what is really going on, and propose the highest-leverage intervention.