Na, that's only really a problem with coiled rear ends, even then a good metal shock like Old Man Emu acts like a limiting strap.
A leaf spring doesn't let everything fall away like a coil which I've had completely unseat by as much as 6" on the TJ
We used to throw the rear sway bar on an XJ since all it did was hinder flex. The additional body roll without it was negligable but it IS a lot lighter a vehicle, however, the H3 rear swaybar is pretty narrrow diameter so I'll wager the roll isn't too bad.
Who's going to be the first to try it
-C