What this paper finds

• Five statistics commonly used to size an AI business case failed verification and are published here as refuted — including a widely-quoted “28 weeks to productivity” figure that appears nowhere in the report it is attributed to.
• Measured gains are real: 40% less time on writing tasks, 26% more developer tasks completed, 15% more support issues resolved per hour.
• But the effect reverses with expertise. Experienced developers were measured 19% slower with AI while believing they were 20% faster.