what ive understood is that to think of the front half of the leaf as a "lower control arm" and the rear as the "spring" (in a corner/handing aspect)
so running a front solid would indeed cause it to bind under extreme conditions, hence the reason for the cat-5 leafs with the spherical bushings.
http://www.globalwest.net/l-11cat5.html
or so ive been told.
