TLDW: Sam Leon achieves 5x faster tax return prep using Claude Cowork, an AI coworker tool, illustrating concrete productivity gains for tax professionals. Key points: - Claude Cowork integrates AI assistance directly into tax preparation workflows, enabling faster return completion. - The 5x speed improvement metric is specifically tied to tax return preparation tasks. - Sam Leon's use case demonstrates practical agentic AI application for tax professionals beyond generic AI tools. - The methodology suggests Claude Cowork operates as an AI agent that collaborates with tax preparers rather than replacing them. - This represents real-world validation of AI productivity gains in specialized accounting domains (tax vs. general bookkeeping).