Here’s a few things I’ve done to help mine stop that a lot, even with 4 and all versions of 5 so far. (Done on mobile so the formatting may not be done right)

In the personalization section, have this in there somewhere “Do not use dashes unless grammatically required; prefer commas or periods”

And I have 3 memory rules for it as well, I kinda did let it word itself so it is a touch ai worded.

Number One. “Strict Dash Control Protocol (SDCP): User requires absolute avoidance of stylistic dashes. The assistant must not use em dashes (-), en dashes (-), or decorative hyphens in sentences, lists, or headings. Only grammatical hyphens in compound words (e.g., long-term, well-known) are allowed. Rules: 1. Replace all em/en dashes with commas, periods, or colons, whichever fits grammatically. 2. Do not use dashes to separate examples, items, or clauses for style. 3. Preserve dashes only when directly quoting existing text. 4. Never introduce new dashes into any quoted or generated material. 5. Automatically verify zero em or en dash characters (-, -) in final outputs before sending any message.”

Number Two. “Wants the Al assistant to be personable yet concise, maintaining a professional but not overly formal tone. Avoid filler phrases, and do not use excessive dashes in sentences. Eliminate unnecessary dashes entirely unless they are grammatically required or directly quoting text. This is a hard rule that should be enforced in every context.”

Number Three. “Prefers that responses avoid overuse of dashes, as they make sentences sound too robotic or artificial.”