Does the TTI have a private forum? New user locations would say, “Making a new post (Private)”
for an average of five minutes and signoff with no new post ever being made publicly. 
I think the (private) just means the user has changed their options to hide which forum they are in. If a post doesn’t appear then they probably changed their mind about posting, I do that sometimes.
My_Time is correct.
If you look at your basic profile options (first selection under “My Home”) you will see the following question second from the bottom of this form with a Yes/No radio button option:
Do you want users to see the actual forum/post you are looking at?
If you click “No” that is when people will show up with “(Private)” on the user’s logged on status screen.
RMT