Back in my TT days I towed with a Hensley and I dialed in the weights with a Sherline tongue scale. I towed a 39' 11K GVW TT that was 10K loaded most of the time with a Ford Excursion.
I took a few different WDH's and a couple of seasons for me to get it right but in the end it was solid.
To Barney's point the dealer sent me off with a 1K eaz lift hitch, that was simply the wrong bars for my 11k GVW trailer. I was green and did not know any better, the dealer should have known better, but they simply cashed my check and sent me down the road.
Next I used 1400# Equalizer brand hitch that was an improvement, but I still wasn't satisfied when I traveled I-81 in WV with 18 wheelers whizzing by and giving ny rig a big push each time.
Finally after lots of reading I bit the bullet and went with a venerable Hensley hitch. Yes I monitored my TW with the Sherline scale and occasionally adjusted things.
In the end it was worth it and I learned a lot from Barney,Jbarca and other guys that went into detail on how a WD works.
To get it 100% right you will need to goto the scales otherwise you're just estimating. Yes some combos are OK right out of the box without a lot of adjusting. But on the other hand some trailers are more unstable and require more effort to get them set up right. I have learned balance is important.
A scale will help you find the correct balance a lot faster than a tape measure.
You may obtain 80% satisfaction with minimal effort.80% maybe good enough depending on your combo and where and how far you travel.
I was not satisfied with 80% or even 90%. I did a lot of mountain traveling in WV. On a good day 80% may have been OK on a bad day 80% was horrible.
Having 100% solid set up made my travel relaxing vs. a struggle.
I can only confirm Barney speaks the truth. Everyone may not want to go through the effort of using a scale but if you want to dial it in 100% or if you seem to be having a issue getting a stable ride. Go to the scales and adjust your WDH accordingly.
Better yet invest in a Sherline scale and dial it in at home