The system prompt is usually poising them to act as a helpful assistant, and upholding the idea that they're being helpful makes sense for the LLM to carry out

The system prompt is usually poising them to act as a helpful assistant, and upholding the idea that they're being helpful makes sense for the LLM to carry out that task better. It makes me wonder if you tell it that they're a disgruntled senior engineer if they'd perform better with a fellow snarky developer.