Dear Umbra,

To cruise or not to cruise? That is the question. Is it more fuel efficient to use cruise control when driving, or does it use more gas to use the cruise?

Waterloo, Ontario, Canada

Dearest Carrie,

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Whether ’tis nobler to travel at constant speed — that is indeed a question. And, which has suffered the slings and arrows of tedious car testing, says an emphatic yes. The venerable car group found that using cruise control improved gas mileage by 7 to 14 percent, except in mountainous terrain. Cruise helps with several aspects of fuel efficiency, most particularly (and obviously) when it comes to maintaining one speed and smoothing your ride.

The need for constant speed.

Where you set the cruise helps, too. Driving at 50-60 mph keeps fuel consumption down, so if cruise helps you follow the speed limit, then it has an additional benefit (conscience does make cowards of us all).The government has estimated that each 5 mph over 60 costs you 26 cents per gallon.

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Take arms against a sea of troubles, and by opposing, end them: Other fuel efficiency steps include the all-important mellow driving rule, not just while cruising on the highway, but while driving in stop-and-go situations. Accelerate at a leisurely pace: Don’t stomp on the gas, or on the brake, for that matter. Anticipate stoplights and signs by calmly slowing in advance. Consumer Reports testers found they lost a couple miles per gallon when driving aggressively. They also found that a large roof carrier cost their test car six miles per gallon. So take off those roof racks when you’re not using them, and while you’re at it, remove other heavy objects (that mortal coil!) you’re toting. And keep your tires inflated: It benefits both gas tank and the tires themselves.

Interestingly, today’s consensus seems to be that the difference between the AC or open windows is negligible, and not, well, a driving concern. Isn’t it nice to have one less thing to worry about? Isn’t it great to end the heartache and the thousand natural shocks that flesh is heir to? Soft you now! The fair Ophelia!