Dear Dr. Gridlock:

I must mention that when many people are leaving room in front of them at red lights, many people in line behind them cannot make their turn.

This happens nightly on Route 3 north at Route 424 in Crofton. Traffic is backed up for at least a mile, with many of us needing to make a right turn onto Route 424 to get home.

Because there are so many people leaving huge gaps ahead of them, it is impossible to get to the right-turn lane. Many people illegally drive up the shoulder.

This is an accident waiting to happen.

Colleen J. Donovan

Crofton

Keep Right, Except to Pass

Dear Dr. Gridlock:

Thanks for trying to persuade people to move to the right and allow faster traffic to pass.

My father and I had the same discussion many times. He insisted on obeying the posted limit but preferred to drive in the fast lane. Then -- surprise -- he complained about the people trying to pass.

I am convinced that drivers like my father create many rolling backups and therefore contribute to many accidents that happen when other drivers try to get through those backups.

Maybe this rule of thumb will make sense to some of your readers (it didn't appeal to my father). It is also the best advice for dealing with tailgaters and very aggressive drivers:

"You should probably move over if the car in front of you is farther away than the car behind you."

Chad Littleton

Annapolis

It is virtually impossible to cruise in the left lane here without someone going faster, wanting to pass. We need to keep that lane open for passing.

Boston-Bound in a U-Haul

Dear Dr. Gridlock:

I have two questions: How long do you believe it would take to travel from Baltimore to Boston on your recommended alternate route, and would you recommend driving a small U-Haul truck on this route?

Barry Smith

Ellicott City

I've done it with a U-Haul. From western Fairfax County to Boston, it took about 10 hours. For you, it would probably be an hour less. Take the Baltimore Beltway to Interstate 83 north to Interstate 81 (near Harrisburg, Pa.) to Interstate 84 east (at Scranton, Pa.) to the eastbound Massachusetts Turnpike (Interstate 90) at Sturbridge, Mass.

The advantage of this route is you avoid the tolls in the Interstate 95 corridor, plus the scenery is better and the roads (generally) are less congested. It's interstate highways all the way, and you should have no problem with a U-Haul.

More on D.C. Plates

Dear Dr. Gridlock:

I can explain the presence of so many D.C. license plates traveling with the rush hour flow in Southern Maryland: Former District residents who have recently moved to Southern Maryland. I am one of them. I was fortunate enough to change my plates right after I moved, but I suspect that many new residents have not had the chance.

There are also a lot of Charles County residents who have relatives in the District, and they may be visiting them.

I can tell you that they aren't keeping the D.C. plates for insurance discounts. My rates dropped about 30 percent when I moved from the District to Waldorf.

Kareem Murphy

Waldorf

Thank you. Any other explanations?

Legal, but Worrisome

Dear Dr. Gridlock:

I live in St. Mary's County. Often on the one-lane roads, I see vehicles passing stopped vehicles on the shoulder. For instance, with a vehicle stopped to turn left, trailing vehicles will pass on right shoulder. Is this legal?

I like to wait for the car to make its turn. I have seen pedestrians, cyclists and other vehicles put in grave peril by these passers. It's done day or night, rain or shine.

Wayne Berry

St. Mary's City

A spokesman for the Maryland State Police, Sgt. Thorny Rouse, said motorists can use the shoulder to go around stopped cars, such as in the example you cite above.

But it is illegal in Maryland to drive on the shoulder for other purposes, such as jumping ahead of slowed traffic or exiting before the exit ramp begins.

Transportation researcher Diane Mattingly contributed to this column.

Dr. Gridlock appears Sunday in the Metro section and Thursday in Anne Arundel Extra. You can write to Dr. Gridlock, 1150 15th St. NW, Washington, D.C. 20071. He prefers to receive e-mail, at drgridlock@washpost.com, or faxes, at 703-352-3908. Please include your full name, town, county and day and evening phone numbers. Dr. Gridlock cannot take phone calls.