Okay.
On the engineering, you got into an interesting question about clearances and specs, about changes in thickness, for example, of a particular tanker car. I guess I'm speculating about new designs down the road. If you were to change the thickness, it could affect the capacity or the effect of a car on a track, for example, or anything like that. Are there limitations to new design going forward that might have unintended consequences?
If we have thicker, heavier cars, I'm worried about what the effect would be on a railbed or whether that would extend the length of a train. Everything has trade-offs. Can you take us through a little of that?