What actually helps
Being specific about the OUTPUT expectations (format, depth, audience). Assigning a persona is a shorthand for those expectations.
Advertisement
What doesn't
'You are the world's best…' — pure vibes. Model doesn't magically become better. Overpraising personas may induce sycophancy.
Advertisement
Concrete use
'Explain in terms a backend engineer would understand.' 'Respond as if writing for the security team.' Audience specification is the real signal.
Multi-persona
Simulate multiple experts debating (Multi-persona / Society of Mind). Useful for exploring perspectives.