"The greater the masses, the more crash energy that must be dissipated"… Absolutely correct. And that's why I am still wondering about the sanity of those guys who came up with the original FRA "standards", because they rely on elastic deformation, which, as we all know has only minimal energy dissipation. The consequence is that the surviving potential in a FRA-compliant car is considerably worse than in a car with elements allowing for a plastic deformation (as to be compliant with UIC standards).

This could bring us back to the Talgo accident in Washington state. I barely dare to imagine how Amcans would have performed in that situation…