Jeepman, I just got from the Yukon, where I met Sargent Preston and his dog King, and I'll need a little time to catch my breath.
That being said, a couple of things:
1. The sway bar twists in response to a wheel hitting a bump. The twist is transmitted to the other wheel. Whether the bushing captures the bar and adds to the twist stiffness of the sway bar, I don't think that really, really makes a difference. If you compare the twist stiffness of the sway bar to the rubber bushing, the rubber bushing is a non-player.
2. The bushings are there to prevent up/down and fwd/back motion, or a combination of both.
3. If Chrysler actually wanted to trap the sway bar in the bushing, they would have splined the bushing and the bar.
4. For a normal rubber bushing and a metal sway bar, what you hear is 'stick/slip'. The bushing holds the bar until it can't anymore, and you hear the noise made when the bar twists free of the bushing.
5. Regarding hard urethane bushings, the manufacturers make no pretense about being able to prevent the bar from twisting in the bushing, especially with the OEM bushing clamp. As it would impossible to generate enough clamping force on the bushing. As such, grease the bushing, and the whole thing becomes a non-issue. The hard bushing better prevents the up/down and fwd/back movement of the bar.
After all that, I'm going back to the Yukon, especially now that Canada has opened its borders!