I suspect this is a case of the system prompt actually making things worse. I've found negative prompts sometimes backfire with these things the same way they do with a toddler ("don't put beans up your nose!"). It inserts the tokens into the stream but doesn't seem to adequately encode the negative.
I know, I suspect that too. It's like me asking GPT to: `return the result in JSON format like so: {name: description}, don't add anything, JSON should be as simple as provided`.
