> But this verification loop exists in a closed world. No equivalent exists for most programming disciplines.

You can do N-version programming with coding agents and you get tests for free. It is easier to implement something than to test the same thing. This approach turns implementing into automated oracle for testing, takes less time (can implement in parallel), and every divergence between versions is either a bug fix or a requirement clarification. In order to make the N-versions more diverse we can use different model providers, programming language or libraries.