[gburlison]

I do not think you are overlooking anything. Drawing GE-09040 shows an example of how the trailer hitch should be attached using bolts that are at least 1.25 in long. Since the bolts have to be removed during the inspection process to weigh the robot with out the trailer hitch, I think the GDC assumes that you will not attach the bolts to the robot during the inspection process and instead will just weigh them with the rest of the robot. I think this is a simple case of the GDC assuming that anything that counts in the weight of the robot must count in the volume of the robot and not catching this obvious exception. I would submit the question.