The information I have gathered says the WD hitch is adjusted so the TT and TV sit level and the fender wells return to near their pre-load heights. Mine are about 3/4" difference.
If you know the weight of the TV without the TT. and you know the weight when you add the TT. You know the amount of tongue weight transferred by the WD hitch and the TT weight.
If you add those two you know the total weight of the TT and can calculate the percent of tongue weight.
This is perhaps not as accurate as weighing the TT without the draw bars but I am interested in weight distribution is when traveling with the WD bars attached.
The amount of tongue weight transferred back to the TT by the WD hitch is interesting but I really only care about the tongue load when traveling.
Also keep in mind that the CAT scale readout is only a snapshot in time. Over the course of your trip you can easily swing 200 to 300 lbs. by adding and subtracting the consumables such as gasoline, water, LP, food etc. not to mention the items that start out in the TT storage hold and end up in the back of the truck.
Generally speaking, if you are close to your max cargo limit you increase the wear and tear more quickly. As to the actual ride, that is such a personal issue it is hard for another to judge.
Safe travels