[mitchellh]

Hey there. Disclaimer: one of the creators of Terraform

I wanted to apologize that this is super confusing. All the scenarios where this exists (there are many) are historical. We originally went with the "nested" approach and now prefer the "split" approach for good reasons shown to us by users. But we kept both for backwards compatibility reasons. We have no good mechanism to enforce a migration at the moment. There are a couple ways we can resolve this technically in the future. For now, we should probably make sure the docs are annotated in all situations of the limitations of nested vs. standalone. I'll mention this to the team!