Persona-Capability Dissociation

Expert personas don’t unlock latent model capabilities. Telling a model “you are a world-class physics expert” doesn’t give it access to physics knowledge it wouldn’t otherwise use.

Across six models and two graduate-level benchmarks (GPQA Diamond, MMLU-Pro), expert personas showed no consistent improvement over baseline prompts with no persona at all. The model’s factual knowledge is already accessible, assigning an expert role doesn’t activate additional capability.

This contradicts widespread prompting guidance that recommends persona assignment as a best practice for improving output quality.

Related: 05-atom—asymmetric-persona-effects, 05-atom—role-constraint-refusal, 07-molecule—elicitation-design-principle