In a recent experiment, Anna Lefour explored the concept of using AI as a stand-in for developers while working on design projects. She created a synthetic developer named Tim, powered by ChatGPT, to simulate the expertise of real colleagues. This was particularly relevant for Lefour, who often felt isolated as a solo designer, especially in fast-paced environments where developers were not always accessible. Tim was designed with a detailed persona, combining traits from two actual developers on her team. Lefour utilized Tim to help structure design discussions and technical constraints, but the results highlighted significant differences between AI assistance and human collaboration. Tim was effective in generating ideas and articulating user needs but fell short in areas requiring context and nuanced understanding. He often provided generic responses and occasionally fabricated details, leading to premature conclusions on technical solutions. In contrast, her real developers brought skeptical curiosity and institutional knowledge to the table. They questioned assumptions, highlighted potential issues, and fostered a collaborative atmosphere that Tim could not replicate. The real developers' ability to engage in deeper discussions and build relationships proved invaluable, emphasizing that while AI can assist in certain tasks, it cannot replace the critical thinking and interpersonal dynamics of human teamwork.