I am way the He!! over my GVWR of 12,300# with 13,960 sitting on 6 tires. But I only add 200# to the front axle when loaded and am under the rear axle rating with 8,780 sitting on the rear duals.
How much weight is sitting on the rear tires? That is the real question.
There should be some common sense used with these ratings.
Example my truck and trailer combined max rating is only around 18K with 3:42 gears. The exact same truck with 4:10's is rated combined at 30K. In my opinion all I am doing is possibly wearing out the drivetrain. My combo weighs 28K.