ChatGPT-5 has been praised as OpenAI’s most “human-sounding” model yet, with sharper reasoning and smoother writing. But how well does it actually perform in business communication? In this article, I test ChatGPT-5 against Writing in Blue Ink’s PCA framework (purpose, clarity, and authenticity). The results reveal where AI can strengthen your writing, and where only the human touch can carry the message.

I’ve signed the Venice Pledge - a global commitment to using AI thoughtfully, transparently, and ethically. As a writer and communications consultant, I use AI as a collaborator in my work, but I believe trust and human judgment must always come first.

Read more about why I signed and how you can join me in building a future where technology serves the public good.

AI tools can make workplace messages look polished, but a new study shows they may also weaken authenticity and trust. At Writing in Blue Ink, we believe strong business communication needs more than polish. It must be grounded in purpose, clarity, and authenticity.