Check the e-mail address on all of the recent positive reviews from Sam, Michael, Gary, JOJO, Craig - it is Worlda's HR department's e-mail address!
Here is some evidence that can be provided: http://www.saet.co.za/jobdetails.aspx?pn=4563
Possibly to automatically alert the management of replies that contain negative reviews?
I think you are definitely right there, it is the same person! http://www.eslteachersboard.com/cgi-bin/forum/index.pl?read=78090
Look at the screenshot!
Normally, this happens only then when a company got a bad review and when the bosses of that company get their paid lackeys to post in their favour.
They are already feeling bad the company has got bad reviews in the past and now think people have forgotten those reviews. The Board is doing us a great service by bringing up all the past posts relating to a particular "school" in the thread. The posters (maybe the same person) think they can deceive us.