Here's also a good read:
http://news.bimmerworld.com/is-a-strut-brace-worth-it/
As mentioned in the article, the deformation/distortion of the chassis will happen over time . By having a strong strut/corner brace will prevent this from happening or at least decrease the severity of it. So, I didn't make these things up and even if you are not feeling it right now, doesn't mean it's not happening, it's a gradual process.