LCA Bushings and Other Bushings
You are correct there is nothing holding that lower from moving to the rear. The poly bushings are not press fit as the standard. The only thing holding the control arm front would be the strut.And that is only the outside of the arm.
I had a poly kit (red) on my Duster. First time I foot braked it I saw red pieces flying out the side. The strut bushings were destroyed.
Maybe if you would shim the torsion bars to hold the control arms front. But would that clip hold it???. I just put the standard bushings back in mine.
They have to be tightened correctly so the bushings can travel the same distance of twist in both directions or they will rip off of the sleeves and you will have the same problem as a poly bushed car. This is done with putting the control arms in the center of travel before tightening the front control arm nut. using the upper and lower bump stops as a locator. make the distance the same upper and lower. Then tighten the nut. The bushings are designed to travel a certain distance before tearing. You want them to travel the same distance in each direction, This goes for every pressed bushings even the uppers. This process does make a difference.