Stabillity(in a tow vehicle) = the resistance to trailer induced sway.
Hensley arrow - geometric hitch perfection.
It works by making the trailer think it's a fifth wheel.
For all the other folks, that use a "bumper pull",
the most important thing is side wall stiffness of the TV tires.
This is(are) the point(s) where the TV resists the induced sway.
The second thing is Ratio of over hang to wheelbase.
Most pickps have 4' overhang.
That is the distance from the rear axle center to the hitch.
120" wheelbase with 48" overhang,
you get 2-1/2 times the leverage to resist sway.
140" wheelbase you get almost 3 to 1 resistance
160" wheelbase you get 3-1/3 to 1 leverage to resist.
But, only if you have the proper air pressure and tire sidewall stiffness.
The rear TV tires are the fulcrum of all induced sway, not the ball/hitch.
Now remember that one of the members stated that his Astro van was one of the finest TV's he had ever driven. That is due to the extreame short overhang. Less than 3'. so, An Astro with 120" wheelbase and 36" overhang,
will tow and be as stable as a quadcab longbed, ratio 3-1/3 to 1, but much easier to park.
So Why is a Tahoe a poor TV, Fluffy tires for a good ride and 2-1/2 to 1 ratio, not enought resistence to sway.
Twitchey, scarey, don't lose focus, ever.
So for fun, put your gloves on first, go grab the towball and push it left and right. Get in to the frequency of the TV, try to make it sway. If you can make your TV move more than an inch either way, you have a problem.
Trailers don't sway, they only go where they're towed.
So, does anyone remember the way to test shocks?
You stand on the bumper, step off, and if the vehicle rebounds more than once, your shocks are bad. Same thing with the towball, if your vehicle wiggles to readily, it is gonna sway to much.
And you can test a TV before you buy it.