This could be exciting stuff. Just like the nuclear industry, they just keep increasing the loading until things break. Nobody does physics. I'm thinking you have wonderful physics when you have huge lines of oil train cars. A bit like rolling a fresh egg instead of a hard-boiled one.
So, if you just keep increasing the speed, I'm thinking of dynamic waves travelling through the entire length. Up, down, sideways. At some point the waves meet and a car jumps off the rail. Sure, they'll reduce the speed for a while, but when nothing happens, the economic pressure to increase the speed brings everything back up again.
When something happens at the nuclear plant, they turn it down for a while, but it all comes back.
Think of the economic cost of slowing the trains to a crawl. Wouldn't you want to put on some monitoring? Wouldn't you want to introduce damping to the cars? Nope.
Now, the philosphers would say that all the physics was done in 1850 in a jar. But we have scaling effects and the real world. Sometimes you have to do things at full scale. Nope.