Great thread (I seldom have time to review the Jeep Forum). The comment about designing in a flat roll axis for stability is hard to dispute. The comment about the desire for a high roll axis needs to be tempered with the drawbacks of the design attribute (another debate like the anti-squat percentage question).

The roll axis height compared to the CG height determines the compliance of the suspension system during cornering and sidehills. A low roll axis will tend to allow chassis lean in cornering and on side hills. A high roll axis, close to the CG height will lose suspension compliance (make for a stiff ride) in cornering and impact vehicle control on side hills (minimal telegraphing of sprung chassis lean before the rollover limit is exceeded). Raise the roll axis above the CG elevation and you risk jacking of the suspension on side hills and cornering (folding the suspension under the chassis, time for the limit strap).

Paved track racers design the roll axis to be as low as possible (track height elevation) for suspension compliance to keep the tires in contact with the track surface at the traction limit, and employ anti-roll bars for chassis roll control. These racers do not exploit wheel travel (too much risk of tire traction patch misalignment) and demand the design to provide the suspension compliance during the short duration that high cornering and impact loads stress the tire contact patch.

The same low roll axis design on a long travel rock crawler without anti-sway bars will flop over on side hills. Fit the crawler with anti-sway bars and it will lose articulation. The crawler seldom experiences high tire stress, and the driver does not need the same level of feedback at the traction limit (the flotation tires already limit the traction). A crawler design can trade traction limit control for the stability gained by a higher roll axis. The compromise is to raise the roll axis high enough to balance the need for roll feedback and compliance with sidehill stability. Sometimes a light anti-sway bar (Anti-Rock bar) with a moderately low roll axis is a good compromise to allow the downhill suspension to work the suspension rather than the links on sidehill challenges.

Off-road endrance racers also do not need as much high speed cornering control at the traction limit (as a paved trach racer, the tires do not bite dirt as hard as pavement), and as a result can trade long wheel travel for roll compliance (more travel can allow for a higher roll axis, within reason, without risk of high speed suspension jacking over rough terrain). The same basic rules to maximize tire traction apply (same as paved track racing) with the compromise demanded of wild axle steer and misalignment (something that is impacted by long travel suspension).

Any thoughts?