Agent can do comment for internal person as well as external person while doing workflow state transition. But right now Agent can't do comment in both tab at a particular stage of the workflow at a time. So Agent needs to go to comment box again and do comment. After then he can process further for next stage transition of the workflow. So if same comment box provides the facility to do comments simultaneously "Internal" as well as "Response to Customer", it would be easy for the agents.
