'Defensive driving' if I do it, 'road rage' if you do it

Such rosy subjectivity is great for warding off depression but lousy for mitigating conflict. Nearly all of us walk around -- or drive around -- with a blind spot to our own missteps. Add the stress of traffic and it's a quick recipe for road rage -- and a great way to lose your affordable insurance premiums.

"Driving is the most dangerous thing people do on a regular basis," James says. "When there's a near miss or mistakes are made, the stakes are much higher. So this tends to raise the level of emotion quite a bit."

When James surveys drivers, on average they admit to driving aggressively 30% of the time. But they say that others drive aggressively 80% of the time.

"Clearly there is a 50% gap in awareness among drivers about their own aggressiveness," he says. "We do not, without training ourselves, observe our own driving mistakes."

Those who want to rid the roads of those awful other drivers should start with themselves, says James.

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"In my case, I realize I am not such a good driver because my wife, who is the passenger, started pointing my mistakes out to me," he says. One of his occasional oversights: forgetting to turn off the turn signal. Have you done that?

Small oversights -- failing to signal every highway lane change, following too closely, merging imperfectly -- make you that other, "aggressive" driver, he says.

People "don't understand this fundamental thing: It's aggressive because it threatens other people. . . . It increases the risk factor."

This article was reported by Karen Aho for CarInsurance.com.