Don't think for a minute that the "tugging" method is foolproof. I have witnessed several trailers being dropped after the driver "tugged" on it. Also, I know of a case where the driver "tugged" and then got under the trailer and looked at the "jaws", pulled away from the dock and "BANG", trailer hit the ground, it can happen. Years ago, Overnite had a MB Mack in Waynesboro that the 5th wheel would stay hooked for several weeks and then the thing would come unhooked without any apparent reason. So, don' t call the driver "dumb", it could happen to you.