Tongue weight and truck carrying capacity

Empty Nest, Soon wrote:
With the current truck the max towable weight is a generous 10,000 pounds, but the carrying capacity is only 1444 pounds. Figuring the weight of two large adults as passengers, etc., I’m left with only about 1000 pounds, or less, of carrying capacity available for tongue weight.

You'll need to deduct the weight of a WDH and anything else not included in the weight of the TV when it left the factory. Let's assume the remaining available payload is 800#.

In figuring carrying capacity of the truck, do I consider the weight of the tongue with TT loaded?

Or do I consider only the weight added to the truck after the WD hitch has transferred some of the tongue weight to the TT wheels? If I use this figure, then how much of the tongue weight should I expect the WD hitch to transfer back to the TT wheels?

With WD applied, you can assume the vertical load added to the hitch is equal to about 80% of the TT's loaded tongue weight.
Then with 800# of available payload, the maximum allowable TW would be 800/0.80 = 1000#.
Assuming a TW% of 13%, the corresponding maximum allowable loaded TT weight would be 1000/0.13 = about 7700#.

Ron