An additional note to my post in the other thread:
when I finally decided to weight the rig, I discovered I was UNDER the GAWR (front); GAWR (rear), the GVWR (truck and trailer) and the GAWR (trailer axles.
I was WAY under the registered max GVW of the truck.
Since the total max load for the tires was more than the GAWR, it was obviously under that rating also.
HOWEVER, I was 3,160 lbs OVER the GCWR of the truck!
Since nothing bent; nothing broke; there had been no accidents, incidents, or occurrences; and nobody was injured or died; I decided that the numbers just weren't worth worrying about (I had been towing the rig for over 2 years by then).