Comment by didibus

What I understand they did is.

You have two tasks:

    - Task 1 - 3h
    - Task 2 - 1h

You ask the dev to estimate both.

Then you randomly tell the dev, ok do Task 1 without AI, and Task 2 with AI.

Then you measure the actual time it took.

Their estimate for AI task missed the mark by 19%, but those without AI were done 20% faster then estimated.

At the time of estimating they didn't know if the task would need to be done with AI or not.