AI Engineering Productivity is Anything But Normal

AI engineering productivity outcomes cluster in three tiers: a mean of 20-46% from distributing an IDE, a frontier of 2.5-3x from companies building the operating layer around agents (Replit, NVIDIA, Amplitude, Anthropic), & a factory tier at 8x+ where agents operate as first-class organizational units (Nubank with Devin). The gap is not the model but the operating discipline built around it.