[Egon]

Someone correct me if I am wrong on this but the only thing that could be changed to minimize (but not necessarily prevent) this would have been stronger valve springs, or a lighter valve train all of which are very expensive. Your engine's valves were traveling so fast that the the valve springs were not strong enough to close them in time as the piston was coming up in the compression or exhaust stroke. The valves were essentially "floating" open and when the valve came in contact with the top of the piston something got bent. Most likely a valve or pushrod. Depending on the severity of the overrev there could also be damage to the pistons, heads or even cam and timing chain. That is why it is called a "money shift."

I am also sorry to say that this will most likely not be covered under warranty and it probably will be expensive.