Well Sir, (OP)
I did weigh our coach, but for numerous reasons. The first time I did it was because I was about to install what's called a "Hydralift" motorcycle lift/carrier on the back of it. So, I wanted some true and actual weights to know just what I was dealing with prior to the install.
Then, after the install, and, over 8,000 miles of carrying our 2008 Honda GL 1800 Goldwing on the back, a mere 900 lbs., and, by the way, the lift was 300 lbs., I weighed it again, all loaded down. It came out over 3,000 lbs. over the actual rear axle weight limit.
So, we decided to make some major changes. But, to answer your question, I did the weight thing for the carrying of the bike and, to have specific tire pressures pertaining to the actual tires I have in relation to the actual weight. Turns out, I was running way too much pressure for the weight without the lift and the bike. This rig rides so much better now.
Scott