Ron,
I added a clarifying statement in blue above. Since the truck is being supported by springs (suspension) each TV may react different pending the rigidness of the rear suspension compared to the TT TW.
And a point to clarify, there was "no" TT tongue jack to the ground when I was describing this. Both of us never stated if the jack was up or down when we where tensioning the urethane springs. If the jack was down, odds are higher the ball will drop down first as the truck will compress easier in most cases. If the jack was up then it depends on the stiffness of the suspension on if the tongue will rise or the ball will drop.
The net end result would be the same the ball is seated in the lower rear part of the latch with no clearance left under the bottom rear part of the tow ball.
A better way to state this is the ball moved "towards" the lower latch sphere and stopped when no clearance was left. Which part is moving up or down "when" depends on a few other variables being in the equation.
Thanks
John