I hate to break it to you but it's not, not completely anyway. Last year I was there and watch them set up the survey for me before I took it. It went something like this region>district>store>workcenter. Understand I come from an low volume store where we have very small teams. So they know your workcenter, then if you opt to fill out the gender and ethnicity questions well they can narrow it down pretty good. If you are the only male or woman in a workcenter, they got you. Even if you opt out of the gender, ethnicity etc. unless your whole team is disgruntled just from knowing personalities you could tell who is rocking the boat. Also I'm sure they are time stamped and how hard would it be for someone in HR to write down the time the test was taken down next to the TM name?