. . . a few nuggets from Traffic: Why We Drive The Way We Do (and What It Says About Us).
SUVs are hugely costly to society. Because they are long and sluggish, they spend much more time getting rolling from a stop at a red light. This is one reason that our city traffic has slowed down. SUV drivers sit higher from the optical rush of the road so they are more likely to speed (just as you wouldn’t have a strong sensation of speed in an airplane 1000′ above the ground, though the airplane is moving at 4X the speed of a car). SUV drivers in at least two countries studied are less likely to wear seatbelts, more likely to be talking on a mobile phone, and less likely to have both hands on the wheel. They crash constantly and are statistically less safe than a minivan that is lighter weight. . . .
Signs are basically useless, especially as they have been layered onto our roads year after year. People drive slower around curves with no “curve warning 30 mph” sign than they do with the sign. Deer crossing signs do nothing to reduce the prevalence of deer-car collisions.