Quote: ...(2) not enough adjustability in factory stock form to take full advantage of modern tire technology, and ...
Not true. There's people that have got 1-3 degrees caster with stock geometry bushing.
The GM A-body guys have a tough time getting to 2-3 deg positive caster because the UCA dogbone will hit the steering shaft.
When I just service replaced my UCA bushing with the rubber offset Moog's I can get MORE caster and camber than a GM A-body with stock UCA's with any bushing installed.