SImple, there not designed to take the forces in that plane.
Struts are designed to work against each end of the bar, not take forces from outside the bar.
Like other people have said it's not made for that force, at 30 mph a typical hard stopping crash and ure looking at pulling around 7g, so think if you weigh 70 kilos like me, and I'm fairly light, ure looking at asking that strut brace to take 490kg of force, and thts at 30, good luck with that!