How can CMOs use narrative engineering to ensure that proprietary technological advantage remains visible, meaningful, strategically differentiated, and economically valuable as commoditisation rewrites the rules of competition? The central insight of this article is not technology. It is commoditisation. Most executives are still focused on building better products, better features, better customer experiences, and better go-to-market execution. Yet the defining strategic reality of the AI era is that products are becoming easier to replicate, features are becoming cheaper to imitate, and differentiation cycles are collapsing. That shifts the strategic question from: "How do we build a better product?" To: "How do we build something competitors cannot replicate, regardless of how much capital they deploy?" That is a board-level question. That is a CEO question. That is a national competitiveness question.