My owners manual doesn't even mention weight distribution hitches, nor does the towing supplement. The only reference would be the hitch manual. The hitch manual wants the front height at least half way back to the unhitched height.
On my truck there is zero difference in steering with or without the WDH, and it's the same towing or not. The biggest difference the WDH makes is porpoising.
With 1250lbs of TW, an 18" shank, and a 160" wheelbase I don't want to see the kind of strain needed to put the front axle back at the unladen weight. The bars already are doing a LOT of work to get me to 50-60%.
Before I changed a few things around I was only restoring 200lbs with WDH hooked up and I lost around 900lbs from empty. I am now restoring more with zero change in handling.
The amount of weight that needs to be restored is going to be compleatly dependent on the TV. I wouldn't want my front 700lbs lighter on a LD 1500, but it makes no difference on my 3500. Even restoring only 200lbs I was approx half way on height adjustment, the extra weight now didn't move the front that much lower.
YMMV