How to Stop ChatGPT Using Repetitive Writing Patterns

Why Does ChatGPT Do This?

ChatGPT's training data contained enormous volumes of marketing copy, persuasive essays, and brand messaging — all genres where punchy, contrast-driven sentences are rewarded. The RLHF process (where human raters scored outputs) further reinforced this style, because confident and structured writing scored better than plain prose.

The result: ChatGPT defaults to rhetorical flourishes even when you want something plain and direct. The pattern has no official name, but the r/ChatGPT community (1,645 upvotes on the original thread) has dubbed it "AI em-dash syndrome" or simply "the ChatGPT sentence."

The Most Common Patterns to Watch For

• "It's not just X — it's Y." The original offender. Shows up in almost every persuasive or summary response.
• Em-dash mid-sentence pivots. "You need speed — but you also need reliability." Endless variations of this structure.
• Triple-bullet openings. Responses that start with three bullet points regardless of whether a list is appropriate.
• Conclusion summaries. "In summary, …" followed by a restatement of everything already said.
• Hollow affirmations. "Great question!" or "Absolutely!" at the start of a reply — especially in older model versions.

How to Fix It: Custom Instructions

Go to Settings → Personalization → Custom Instructions (or the system prompt in your API/operator setup) and paste the following:

Short version (recommended for most users)

Write plainly and directly. Avoid the "It's not just X — it's Y" sentence pattern. Do not open responses with affirmations like "Great question!" or "Absolutely!". Skip summary conclusions unless I ask for one.

Full version (for writing-heavy workflows)

Writing style rules — follow these in every response:
- No "It's not just X — it's Y" constructions.
- No em-dash pivots used as a rhetorical device.
- No opening with bullet lists unless the request is explicitly a list.
- No filler affirmations (Great question, Absolutely, Certainly, Of course).
- No summary paragraph at the end unless I ask for a summary.
- Prefer active voice. Prefer specific nouns over abstract ones.
- If you are uncertain, say so plainly instead of hedging with "It's worth noting that…"

What If the Pattern Keeps Appearing?

If ChatGPT reverts to old habits mid-conversation, you can nudge it in-chat: "Reminder: plain writing, no rhetorical contrasts." For consistent Custom GPT deployments, embed the style rules directly in the GPT's system prompt — not just in Custom Instructions — since system-prompt rules have stronger precedence.

Also note that the pattern is more pronounced in shorter, summary-style prompts. If you give ChatGPT more context and a specific tone target ("write like an engineer's internal Slack message"), it calibrates away from marketing-speak more reliably.

Does This Affect Quality?

No — suppressing these patterns does not reduce response accuracy. You are only changing surface style, not the underlying reasoning. Most users report that plain-writing instructions produce clearer outputs because ChatGPT is forced to be specific rather than rhetorical.