I think it's fine to consolidate to edxapp_ref.yml, but we'll probably checkin our prod playbook again.
Mainly because we want to get to a state where we can use the unmodified checkout to admin our instances.
We found a way using tag assignments in the AWS console and boolean operations on hosts to make that possible.  I.e. something like
```
- hosts: tag_environment_prod:&tag_function_webserver
```