Ok, we got some impressive emails and feedback since the weekend on the new stat features for every message. We added a new one. When looking at a message, the third parameter over there tells the entire number of message reads for the entire thread. Thus, when clicking on it, you have the entire view of the thread. A new field is present for that report which is the message ID. Thus, you can order by message ID to view the progression of the thread reading, see which one read which messages of the thread and so on.