Dear Dr. Gridlock:

You recently wondered why drivers find it relatively easy to merge from two lanes to one entering the District on I-295 north (Kenilworth Avenue), using the alternate merge approach, as opposed to the cutthroat competition to merge from two lanes to one onto Pennsylvania Avenue SE from the Southeast/Southwest Freeway.

I'm glad you asked. The answer is easy: There is a yellow sign on the ramp to 295 north that simply says, "Alternate Merge," and drivers cooperate by doing the right thing. The other merge has no such sign.

While this should be intuitive, and drivers should not need to be led like sheep to take turns, I'm sure the sign makes all the difference.

If local transportation officials would put "Alternate Merge" signs everywhere that two lanes merge into one, it would soon become part of the local driving culture -- and courtesy.

Thomas C. Hall

Takoma Park

What you say makes plenty of sense, Mr. Hall. I'm going to mention the idea to local transportation officials. Thanks for your observation.

Meanwhile, are there other "Alternate Merge" signs in the metropolitan area, and do they lead to zipper merges in which drivers take turns?

Cruising Out of Control

In the Dr. Gridlock column on Jan. 12, reader Jim Woods of Columbia had a New Year's resolution for all drivers:

"If I am in the far left lane with cruise control set for six to seven miles above the speed limit and a hundred cars blow by on the right traveling 10 to 30 mph above the speed limit, I see no reason to aid and abet those idiots by moving over."

Dr. Gridlock responded with an "Oh, no," because I knew what was coming. Nothing seems to anger our driving population more than a person who cruises in the left lane. Here are some responses:

Dear Dr. Gridlock:

If hundreds of cars are blowing by you on the right, Mr. Woods, YOU are impeding the flow of traffic, regardless of whether the other cars are exceeding the speed limit more than you are.

"Slower traffic keep right" and "Keep right except to pass" are the rules of the road. What you accomplish by not letting traffic past is to create a potentially dangerous situation, making other drivers become angry and possibly aggressive.

What you are doing, Mr. Woods, is aggressive driving.

Here's a New Year's resolution of my own: Resolved, that law enforcement recognizes drivers like Woods and tickets them for impeding the flow of traffic, failure to keep right except to pass, aggressive driving and maybe even unauthorized law enforcement.

Adrian Andreassi

Chevy Chase

Dear Dr. Gridlock:

Writer Jim Woods of Columbia boasted that he cruises in the left lane. The smug tone of his remarks proves the adage that the average man is absolutely convinced he is a better-than-average driver.

He also confirms the old joke that "everyone who drives faster than I do is an idiot, and everyone who drives slower than I do is a moron."

No one will ever convince him he is wrong, but this much is clear: In almost every state, what he does is illegal. The left lane is for passing, not cruising.

In my opinion, drivers who are not very sure of their talent prefer the left-most lane because there they will have to contend with fewer cars entering and leaving the lane. But some others clearly enjoy the self-righteousness of enforcing some sort of speed limit on those who choose to drive faster.

Doug Ellice

Bethesda

Dear Dr. Gridlock:

Having lived in Southern Maryland for 13 years, I continue to be amazed at the number of left-lane drivers.

Some drivers appear to believe that there is a law requiring you to drive in the left (passing) lane if you're going to turn left within the next 30 miles.

I frequently see drivers in the passing lane when they're the only car on the road, or going slower than traffic in the right lane or (worst of all) going the same speed as traffic in the right lane -- essentially providing a rolling roadblock prohibiting cars from passing in either lane.

These drivers seem oblivious to tailgaters trying to give them a message.

Could you please poll your readers who are left-lane drivers to see why they do this? Maybe if I can understand why they do this I'd have more patience with them.

Note: Pennsylvania passed a law making it illegal to travel in the passing lane unless passing a car in the right lane or turning left within the next two miles. Maryland should do likewise.

Mark A. Geckle

Lusby

Virginia has a law that requires left-lane drivers to move over if being overtaken by another vehicle signaling intent by flashing lights or honking horns.

Why won't left-lane cruisers move over?

Dear Dr. Gridlock:

After reading your Jan. 12 column, I have to propose my own 2003 resolution:

Be it resolved that the ambulance delayed at the end of a train of cars in the left lane of the Beltway, behind Jim Woods who sets his cruise control at 6 to 7 mph over the speed limit in that lane and sees no reason to abet "those idiots" by moving over, be responding to an emergency call from the Woods residence.

J.M. Geiger

Vienna

Transportation researcher Diane Mattingly contributed to this column.

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