We're out in public, in our cars. Back at the office it's easy to observe the ebb and flow of emotion and communication. Bring ten people to a sixty-minute meeting. There's no problem unless someone starts snoring or yelling. Back on the highway it's a problem all the time since we can't use our vehicles to communicate. These things are not cell phones or web logs or Facebook entries. I can drift over into your lane or ride too close to your bumper. Can you tell when I did that deliberately? If you give me a bigger vehicle it's harder for me to see around the perimeter, know what's outside my field of view. If I drive more aggessively perhaps that will keep the innocents out of harm's way.