Dear Dr. Gridlock:

Keeping slower cars to the right and using the left lanes only to pass is one of the most important and effective driving principles in safely and efficiently moving traffic along our crowded roads.

Although I will not go as far as saying that this area has an inordinate number of left-lane "squatters," I agree there is an unusually large number of left-lane exit ramps and left-lane on-ramp merges.

Some highway engineers have clearly ignored long-established practices to save a few bucks. The long-term consequences of such poor decisions will be increased congestion and more accidents as slow traffic moves left to exit and faster traffic passes to the right -- both major no-no's.

Andrew Chen

Clarksville

XM Radio

Dear Dr. Gridlock:

I was happy to see your suggestion of XM Satellite Radio for its 24-hour traffic updates [Dr. Gridlock, April 8]. I began subscribing to it six months ago and have never thought twice about the $9.95 monthly fee.

I carry the portable unit from my home stereo to my car to my office. I listen to it all day. I always find a station to suit my mood.

The addition of XM instant traffic and weather has been great. Once I know the status of my commute, I like to listen to the rush-hour information for other cities -- and, in most cases, be glad I'm not there!

Susan Zelenka

Arlington

For more information, visit www.xmradio.com/index.jsp.

Costly Parking Woes

Dear Dr. Gridlock:

I started parking in the garage at my office building in Northwest Washington. I pay almost $200 a month, three times as much as the cost of commuting on Metro. But I have a new baby and think the ability to get to the caregiver at a moment's notice is worth the additional cost.

Having said that, the parking garage is the most stressful part of my day. Every space, ramp and aisle is so full you can barely drive. I spend 15 to 20 minutes most days waiting for the parking attendants to move cars so I can get mine out.

One day at lunchtime, I went to retrieve something in my car. If there had been an emergency and I had to get to the babysitter's to get my daughter, the attendants would have had to move 15 cars (not in spaces) so I could have gotten mine out.

Mary K. Dillon

Arlington

My sympathies. Contact Commuter Connections, 800-745-RIDE or www.commuterconnections.org. Ask about the guaranteed ride home in emergencies.

If you take public transit or carpool to work, this program will pay for a ride home by taxi or some other method, up to four times a year, for a home emergency or unscheduled overtime.

You can take Metro, or they'll match you up with a carpool, which should be easy in Arlington.

Let me know if this works out.

Parking Dibs

Dear Dr. Gridlock:

This has happened to me twice in the past month, the first time at Tysons Corner Center and the second time at the Tysons Galleria mall.

Parking is always hard to find at either mall, so rather than just drive around aimlessly, I waited in the lot for someone to leave. Each time, someone was returning to the car in the row I was waiting in, and both times, another driver came zooming in from another area of the lot to "claim" the spot.

I have always been under the impression that it was understood that the driver already waiting in that row has dibs on the spot about to open up. I guess no one else told those two.

The first time, the driver drove around me, cut me off and took the spot. The second time, the driver tried the same tactic, but my "dirty look" persuaded her to find another spot.

What's your opinion? Does the person waiting patiently in a row deserve the spot?

Steve Rothenberg

Lansdowne

Yes, but first it must be made clear that the vehicle is waiting for that spot. That can be done by waiting in the aisle, adjacent to the vehicle pulling out, with your turn signal on.

If others aren't sure of your intentions, we can't blame them for their me-first attitude. If they are, shame on them.

Anyone have any other ideas to thwart parking space pilferers?

Helping Visibility

Dear Dr. Gridlock:

It's not the lack of headlights that bothers me during rain, but rather the fact that when the headlights aren't lit, the taillights aren't, either. Taillights are most important during poor visibility.

With all the other safety features required on vehicles today, why not the simple one of automatically turning on headlights (and taillights) when the wipers turn on?

Emil Klingenfus

Manassas

No argument here.

Adding a Lane as Needed

Dear Dr. Gridlock:

I moved to the area in 1995. Since I have been here, there has been a large vehicle of some sort parked on the Theodore Roosevelt Bridge near the E Street exit.

What is that, and why has it been there so long? It does not seem to serve any purpose, except as a distraction.

Alexandra Simpson

Fairfax

Oh, but it does serve a purpose. The machine moves the Jersey barriers in the bridge median to allow for one more lane in the direction of rush-hour traffic.

In the morning, the bridge is four lanes eastbound and three lanes westbound. In the evening, it is four lanes westbound and three eastbound.

That is a huge benefit to Virginia commuters. The bridge is owned by the District. The Virginia Department of Transportation pays for the machine and the driver.

Parking Next to SUVs

Dear Dr. Gridlock:

In your April 8 column, John Horvath wrote that when backing out of a parking space from between two SUVs, "one can see oncoming traffic through tinted windows of vehicles parked next to you."

Because he drives an SUV, he can see through. In my Cavalier, the view is still obstructed, because my windows don't line up with those of an SUV. His other suggestions -- opening a window to listen for oncoming traffic and backing slowly -- are good ones and apply to all vehicles.

Steven Wadding

Beltsville

Driving to Florida

Dear Dr. Gridlock:

You asked for suggestions to break up the Interstate 95 trip to Florida. Here's mine: Drive from the D.C. area to Hardeeville, S.C., right on the Georgia/South Carolina line and home to several budget motels and hotels. That evening, drive into Savannah, Ga., via U.S. Route 17 (about 17 miles) and enjoy dinner and the Savannah night life.

The following morning, drive 22 miles to Hilton Head Island via Route 278 and enjoy a day and evening at the beach.

This alternative places you right next to I-95 for the resumption of your trip, saves a lot of money on the hotel bill and puts you centrally located between a fun day at the beach and a vibrant night life.

If you want to spend only one night in Hardeeville, forgo the beach trip to Hilton Head.

Mike Moore

Herndon

Thank you. I didn't realize that Hilton Head was so close to I-95 corridor. I've stayed in Hardeeville many times and have enjoyed the break there.

Dear Dr. Gridlock:

Your April 11 column discussed alternatives to the Interstate 95 corridor to Florida. I routinely use the I-81 to I-77 route through the Shenandoah Valley, mentioned by a reader, although I usually stop in South Carolina.

I take I-77 to Columbia, S.C., and then head east on I-26 to catch I-95. Once on I-26, it's about one hour to the I-95 interchange. If you stay on I-26 east, it's another hour to Charleston, S.C.

There is one problem with I-81 that your reader didn't mention: It's a major truck route, so much so that I recently read a column about proposed separate lanes for trucks. Even with the trucks, I prefer that route over I-95. The scenery through the mountains is lovely.

An added advantage for me: When I get tired of driving and need a break, there are numerous antique malls along the way; I still haven't been to all of them.

Judy Carroll

Rockville

Thanks for the tips. Given the allure of antiques, I wonder about the cost of the alternate route.

I would still like someone to measure the I-81/I-77 route vs. staying on I-95.

And, yes, the Virginia Department of Transportation is looking at ways to build truck-only lanes on I-81. The trucks are a big problem.

Driving in China

Dear Dr. Gridlock:

I have been to various parts of China -- cities and the countryside -- three times in the past six years. I have witnessed increasing levels of traffic congestion. But I take umbrage at the experiences described by Matt Scout [Dr. Gridlock, April 8].

It is true that Chinese drivers ignore most of the written rules of the road. They occasionally ignore traffic signals and signs. They routinely ignore lane lines.

But in China there is a lot more respect for bicyclists and pedestrians. Motorists drive only as fast as road conditions permit. Also, there is an obvious absence of the American selfish me-first attitude. Everyone gives a little so they can all get there.

Regarding his experience with the driver who sped through the toll booth without paying, Scout might not be aware that government-owned vehicles are not required to pay tolls in China. They do not have to stop, and they are equipped with different license plates for easy identification.

From my experiences, I would argue Chinese drivers are more courteous and conscientious than U.S. drivers.

Let's not judge before we have all the facts.

John O'Bannon

Crofton

Danger for Motorcycles

Dear Dr. Gridlock:

High-intensity discharge lights, or even misaligned headlights, pose significant threats to people on two wheels. Unlike cars, motorcycles do not have a rearview mirror that flips up or down. Also, our side mirrors are a lot closer together. That puts much more glare directly into our eyes and makes it significantly more difficult for us to avoid the lights.

Unfortunately, I sometimes feel the only solution is to adjust a side mirror, which not only eliminates the use of that mirror but also is dangerous to do while riding.

Please remind people to keep their headlights adjusted properly and add my name to the list of people against those lights.

Daniel Hoult

Rockville

I'm on that list, too. Federal officials who gave a green light to these lights should be sentenced to look at them several seconds a day.

Transportation researcher Diane Mattingly contributed to this column.

Dr. Gridlock appears Sunday in the Metro section and Thursday in 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.