I'm not sure how your comment addresses the core problem that risk/distance is not a reasonable metric if long-distance driving is less risky than short-distance driving, and you apply the short-distance driving risk to long-distance driving.
As a passenger on either it doesn't matter where the risk is concentrated . I am only interested in the outcome of how safe my journey is going to be.
As a technology such differentiated metrics helps to understand aspects of flying which is why broken metrics are used by the industry in more focused forums.
But that's exactly my point. As a passenger, it matters if the calculation of how safe your journey is is wrong. And the calculation is wrong if it doesn't take into account how long the drive is.
