The Jagged Frontier: Where Human Judgement Commands a Premium Again

Three years ago, researchers from Harvard and Boston Consulting Group ran one of the most cited field experiments in the short history of AI at work. Hundreds of elite consultants used AI on real tasks, and the results split cleanly in two. Inside the machine\'s zone of competence, AI users outperformed dramatically. Outside it, on tasks deliberately designed to sit just beyond the model\'s reach, AI users did worse than colleagues with no AI at all, because they trusted confident answers that were confidently wrong (Dell\'Acqua et al., 2023). The authors called the boundary between those two zones the jagged frontier.

The finding has only sharpened. Wharton\'s recent work on cognitive surrender shows the same shape in decision-making: when AI errs persuasively, human accuracy drops below the unassisted baseline, and the humans never notice (Shaw and Nave, 2026). The frontier is jagged and constantly moving, which makes it the most important map no executive currently holds.

Scarcity changed address

Here is the strategic consequence almost everyone misses. The jagged frontier is not a limitation of AI. It is the new pricing mechanism for human judgement. Everything inside the frontier is being commoditised at extraordinary speed. Analysis, drafting, synthesis and summarisation are collapsing towards zero cost. Everything outside it, the genuinely novel call made under ambiguity with real consequences, is appreciating just as fast. Scarcity has not disappeared. It has simply changed address, and most careers are still built at the old one.

I put this directly to a Partner at one of the major firms who had brought me in on a client mandate. His teams were faster than they had ever been, and he was quietly worried rather than triumphant. When I asked where his own irreplaceable value now sat, he paused, because the honest answer was that much of what had made him valuable a decade ago was now available to any analyst with a licence. The leaders who thrive from here are the ones who can answer that question without pausing, and who have already moved their reputation to the far side of the frontier.

Position deliberately

In my research across 6,000 executive leaders, the ones who compound value in this environment share a single trait. They know where the frontier sits in their own domain, and they position themselves deliberately on its far side. They let the machine own the commodity zone entirely and concentrate their reputation where the machine fails. That positioning is cognitive agency expressed as career strategy, and it is the foundation of what I measure through the Executive Cognitive Advantage Index.

The executives quietly becoming replaceable are not the ones using AI too little. They are the ones building their reputation inside the commodity zone, where every rival now has the same machine and the same output, and where the only remaining way to compete is price.

My recommendation is singular. Map your own frontier. List the judgements your role exists to make, and test honestly which of them AI now performs to your standard. Then move your visible effort decisively to whatever remains, because that remainder is the whole of your future value.

References

• Dell\'Acqua, F. et al. (2023). Navigating the Jagged Technological Frontier. Harvard Business School Working Paper.
• Shaw, D. and Nave, G. (2026). Thinking Fast, Slow, and Artificial: How AI is Reshaping Human Reasoning and the Rise of Cognitive Surrender. The Wharton School.
• Barker, K. (2026). Hidden Power: How Boards and CEOs Win the AI Era. Amplify.