Well, having a weak link in the steering may be desirable since you are breaking tie rod ends? You can replace them with hardened heims and grade 8 bolts, but then you're more likely to destroy several other expensive parts in the rocks aren't you? You might be better off just slowing down when you encounter those sorts of extreme conditions.
My experiance with heim joints has not been good. They squeak like crazy. You can hose them down with penetrating oil every ride and they will still end up sqeaking bad. If the soil you ride on has any sand at all forget about heims. Mud and water wont be all that great either. If you only ride logging roads or are somewhere quads are street legal they would work great.
Retro your probably right. Around here all it is are rock trails, hardly any just smooth riding unless you go to a park like Brimestone or ride royal blue. Dad has hiem joints on his drag car, so i figured if it would be worth a shot or not to try them.