Once a project is default-cohering, you can hill-climb to improve it.

You get ever more precise requirements, and get ever better and higher fidelity implementations of the requirements.

But this execution playbook cannot find new hills.

You need to have a burst of creativity to create a new kind of thing.

At the beginning it will be rough, messy.

But if it gets to the point of being viable it becomes default-cohering.

Then past that point you can simply optimize it to be a better version of itself.