ORA_SVC_HIDE_OUTBOUND_MSG_TAG expected behaviour

Summary:

Is it correct that the ORA_SVC_HIDE_OUTBOUND_MSG_TAG profile option only hides the message identification number on the messages sent out of HR Help Desk when using the email channel under the Messages tab or using the Compose Email SmartAction? I have enabled this profile value but any email sent using the Start Internal Conversations/ Start Internal Conversations with Details SmartActions in HR Help Desk and the Create Conversation in Case Management SmartAction all still have the message identification number showing on the emails.

If this is correct is there another way to hide this?

Thanks