Hey man, I took the classes. You just have to imagine the suspension, and understand what's really going on. I don't know about yours, but I have steel LCA's that are hollow. There are holes, and I can stick a few fingers inside my LCA. Not very "strong" to me but they don't need to be. The aluminum ones probably have to be thicker because of the properties of aluminum. Just like how aluminum rims are thicker than steel rims. Now that's just the Macpherson strut system, and other similar styles. If the spring is mounted on the LCA, then it's a load carrying control arm. Not the case with struts.
