> someone is going to think waves travel at different speeds That's a good thing, right[1]? Something about "the one thing all models have in common..." comes

> someone is going to think waves travel at different speeds That's a good thing, right[1]? Something about "the one thing all models have in common..." comes to mind. [1] https://en.wikipedia.org/wiki/Velocity_factor https://en.wikipedia.org/wiki/Velocity_factor