Ask him to give you a refresher lesson on a thorough preflight. What he is doing is moving all of the control surfaces by hand through their entire range of travel, making sure they are smooth, and they hit a solid stop at each end of the range of travel. A good thing to do on preflight.
On a PA-28 I stand behind the elevator, grab the tab between my thumb and index finger and move the entire assembly through its range of travel. When you move the elevator up (yoke full back) visually inspect the tab pushrod that goes into the butt hole of the aircraft (for lack of better term
) and look at the bolt and lock nut.