This just tells how to determine the actual gross weight of a vehicle, it says nothing about how a GVWR is determined by a manufacturer.
Correct.
It also tells us the gross weight is the sum of the axle ratings and not the vehicle mfg GVWR number.
How the heck could you give a 10K GVWR to a vehicle that only had a 9K sum of front and rear GAWR's?
??
I have no idea where you came up with that one.
I've made my point about what a GVWR does or doesn't do. Were just repeating ourselves to the point the OP has given up and gone camping.