AI is also excellent at reverse engineering specs from existing code, so you can also ask it to reflect simple iterative changes to the code back into the spec, and use that to guide further development. That doesn't have much of an equivalent in the old Waterfall.

are you intentionally being vague here becuase it's a HN comment and you can't be arsed going into detail?

or do you literally type

> Look at the git repo that took us 2 weeks, re-do it in another fresh repo... do better this time.

I think you don't and that your response is intentional misdirection to pointlessly argue against the planning artifact approach.