Buf if one rod is too short, you'll have to adjust the clevis further or change the way the servo arm is centered on the servo to get both ailerons neutral. If you end up having to change the position of the servo arm on the servo because the rods have a great difference in length then the servo will have less travel in one direction than the other for that particlar torque rod. Pull might be greater and push might be lessened by that. Also, the way a clevis works is to adjust the actual length of the rod in small increments. So we're talking about length that is greater than that of what a clevis can adjust.