Yes I too have found newer models (mostly Opus) to be much better at iterative development. With that being said if I have very strong architectural/developmental steer on what I believe the output should be [mostly for production code where I thoroughly review absolute everything] it’s better to have a documented spec with everything covered rather than trying to clean up via an agent conversation. In the team I’m in we keep all plan.mds for a feature, previously before AI tooling we created/revised these plans in Confluence, so to some degree reworking the plan is more an artefact of the previous process and not necessarily a best practice I don’t think.