This allows project admins more flexibility and reduces the burden on JIRA administrators. There are certain criteria though. They are:
- The workflow must not be shared with any other projects.
- The workflow cannot be the JIRA default system workflow. (because the default cannot be edited!)
There are also restrictions:
- Statuses must already exist.
- Cannot delete statuses.
- Cannot edit existing statuses.
- Cannot delete a status from the workflow.
- No access to selecting or updating screens.
- Cannot edit transition's properties, conditions, validators or post-functions.
To see this in action, make a regular user a project administrator, log in as that user, go to workflows on the project administration page and click on an issue type. That is the key. Then you should see an edit option.