Observing Cars Crashing Into K-Rails, to Debunk a Theory

During my ambulance days, a State Trooper explained to me that K-rails were designed to keep cars stuck to them in the event of a collision (as opposed to ricocheting the car back into traffic, where they would cause mayhem). Have you ever heard this? I was never able to confirm it--no manufacturer makes such a claim--but if we look at the design of K-rails, the physics of their construction seems to back up the Trooper's assertion. However, I'm not convinced, especially after seeing the...