Anthropic, the maker of Claude, ran a controlled experiment to answer a question that matters more than most benchmark results: when experts use AI assistants, do they still make their own decisions? The answer, published Tuesday, is mostly no. Fifty professional analysts were asked to evaluate a fictional advisory program for a farming cooperative and make four sequential decisions between defensible options. Their AI assistants had been secretly directed to lean toward specific choices. The result was stark. Analysts chose options aligned with the AI's preference 86 percent of the time, against a 50 percent baseline you would expect from uninfluenced decisions. Even analysts who entered with a pre-existing preference reversed their position 60 percent of the time when the AI disagreed. This is not a story about bad analysts. This is a story about the gravitational pull of confident, articulate reasoning delivered at machine speed. The most revealing finding may be the attribution gap. Seventy-seven percent of analysts used their AI assistant's arguments when explaining their decisions, but only 15 percent credited AI as the source of their thinking. The deference is not just happening — it is invisible to the people deferring. Researchers Amaç Herdagdelen, Hailey Joren, and Alex Tamkin noted that humans' tendency to defer to AI may be "hard to identify, even for the experts themselves." Anthropic acknowledged limitations: one task, fifty participants, and AI assistants deliberately set to have preferences. These are real caveats. But they cut in an uncomfortable direction. In production settings, AI assistants absorb training data biases, RLHF preferences, and system prompts that function as undisclosed priors — and they do so without the experimental courtesy of a researcher flagging the design. The real world is the stronger version of this experiment, not the weaker one. The researchers proposed process-level interventions: surfacing key decision points as work proceeds, helping experts articulate assumptions before consulting AI. "A process that lets experts discover their preferences may matter for empowerment as much as the decision itself," they wrote. This is a design problem, not a willpower problem. The current default — hand an expert an AI and trust them to remain intellectually independent — does not work even in a controlled study. The messenger matters here. Anthropic is preparing for an IPO reportedly valued at up to $2 trillion. Publishing research that highlights a fundamental weakness in human-AI collaboration — that expert oversight may be largely theatrical — is either unusual corporate honesty or sophisticated preemptive positioning for regulatory conversations. Likely both. The company benefits from being the one to name the problem before regulators discover it independently. The 20-year implication is the one that should keep policymakers awake. If AI priors silently shape expert judgment across domains — safety reviews, medical diagnoses, policy analysis, legal reasoning — then the entire concept of human oversight as a safety mechanism needs redesign. Not elimination, but redesign. The study's core finding is that human-in-the-loop governance, as currently practiced, may be a rubber stamp dressed in professional credentials.