That sounds so crazy and contrary to everywhere I've been in the civilized world that I refuse to believe it (as you have written it) without some chapter and verse citation from the GA traffic code.

If it is literally true, it means that in GA, I can drive down a merge ramp and not even look at what is coming down the freeway; they have to hit their brakes or swerve to adjust to what I'm doing. I'm in a merge lane, which ends, and thus I have priority over anyone in an existing lane that isn't ending!

Any special rules about making it mandatory to let merging vehicles in have to be somehow crafted to they only apply to the obvious situations that they are intended for.

Or they have to apply in special places where signage clearly indicates that two flows are merging such that neither has the right of way. For instance the "Form 1 Lane" traffic sign or whatever. "Form 1 lane" effectively means both lanes are ending, and a new one is starting with equal priority access.

I'm curious as to where this is the law. It was not in the state where I learned to drive.

People merging onto the highway are supposed to reach highway speed before attempting to merge, but they very often do not do that.

And they're supposed to to find a gap, but there may not be one or other drivers may deliberately try to deny them one.

The merging lane may be very short.

The merging car may start to change lanes even if it's not safe to do so.

Congestion may require more deliberately courteous behavior.

The right lane often has many trucks clustered together and rote exercise of the keep-right rule will require an excessive amount of lane changing.

And on a limited access highway, lane changing is the most dangerous routine maneuver so one should be thoughtful of balancing lane changing with expediency.

And the idea that a driver has no responsibility to accommodate another merging driver, if applied strictly, also means that one cannot always leave the right lane at will, because driver in the left lane are not permitting. So you change speed a lot, which is rough on fuel efficiency and precludes cruise control if it's adaptive.

Being religious about keep-right is kind of miserable on a congested highway, especially one with a differential of speed speed limits depending on vehicle type. The people most steadfast about traffic laws get punished at the pleasure of people who flout them, which doesn't seem correct.

One reason for this is that it only takes one person "policing" from the right lane (i.e. driving down the middle of the road, or worse: swerving out in front of the left lane) to shut down zipper merging.

Over here in the netherlands we're phasing these out, crossing traffic at a diagonal like that means that drivers will need to look almost 180 degrees behind them to spot you. It's a fine solution if there's only one lane of cars, but as soon as there's more than one lane merging movements just make it plain too dangerous.

Funny, one of my pet peeves since I moved to the US is the "keep right unless passing" or "left lane is for passing only" or any other variation of the same sermon. Sounds logical at first, but it's really bureocracy.

If the highway is congested, then the rule becomes meaningless. The traffic density is so high, that it's perfectly natural to use all of the available lanes.

If the highway is not congested, then the density is low enough that you should be able to change lanes as necessary, with minimal fuss. If that's the case, then the whole "keep to the right unless passing" is really just a crutch. In this situation, what we really want is something along the lines of "pay attention and don't make people pass you on the right", but that's not enforceable. So we come up with a rule like "keep to the right unless passing", because that can be enforced by cops.

Are there any instances where there isn't signage that informs drivers in advance? I'll drive in the right-most lane and if I see one of those signs, I'll check for traffic, signal and move to the lane to my left.

Having driven both in Europe and the US, this is one of my pet peeves in the US. This causes so much unnecessary risk. I used to chalk this up to the super light driving test in the US (at least compared to Europe).

But recently I realized it's not just driver education: the road UX is different between Europe and the US on main highways. Here in the US, the right lane very often "disappears", i.e. becomes an "exit only" lane. The result is if you're going straight for a while, you find it easier to not stay on the right and then have to change lanes. In Europe, the road design tries to minimize the "vanishing right lane" syndrome: exits ramps are separated; and if need be, it's the left lane that goes.

Drivers soon learn that the rightmost lane often has congestion due to merging cars arriving at the merge point in groups created by off-highway traffic lights, and then tend to avoid driving in the right-most lane. Metering lights on the on-ramps help reduce the grouping, but the angled merges remain, as does the learned behavior.

Also, many US states post signs: “Keep right except to pass” but California posts “Slower traffic keep right” and since nobody wants to identify as “slower” we do not.

Interstate 5 in the Central Valley is generally two lanes, and semi-trucks and vehicles pulling trailers are limited to 55 mph, and must keep right except to pass. Other traffic has a higher speed limit. When traffic is heavy, nobody leaves the left lane because they are much less likely to find a gap to merge into.

And then, invariably, someone behind them will immediately change into the right lane and speed up to pass them on the right. Thereby making it even harder for the person merging to get in, while also pinning the person who made room for them in the middle lane, because there's suddenly a bunch of faster-moving traffic in the right lane.

It will tend to work out this way even when it's a 3-lane highway and the left-hand lane is wide open.

I'm always amazed in the midwest what a difference there is between traffic in states that have (and actually enforce!) a "get out of the left lane" law vs states that don't.

I-80 across the eastern half of Iowa in particular is exhausting to drive on, because a lot of people camp in the left lane and clog up traffic. That leads to desperate and aggressive driving to get around these silly bottlenecks, which kills fuel efficiency and makes the roads more dangerous.

Rule 268 of the Highway Code touches upon this:

> In congested conditions, where adjacent lanes of traffic are moving at similar speeds, traffic in left-hand lanes may sometimes be moving faster than traffic to the right. In these conditions you may keep up with the traffic in your lane even if this means passing traffic in the lane to your right. Do not weave in and out of lanes to overtake.

Ashley Neal's video on motorway driving provides some good examples of when sticking in lane 2 is OK, provided that you continuously observe and anticipate other road users: https://youtu.be/Vo7sNwf80lI?t=766

Would the remark still be equally valid given left-lane driving layout (as opposed to right-lane in the US)? Both left turn merging onto north/south road and right turn merging back onto east/west road strike me as lower risk given attention is focused on a single lane at any given time, as opposed to negotiating both north and south lanes simultaneously in existing intersection.

Also, the area appears to be in a rural location without nearby power distribution infrastructure to tap into; probably not as simple--or cost effective--at first glance.

As a result to this there are more lane splitting episodes (even within the speed limit) in order to finally being able to keep moving at a faster speed because the lane is effectively blocked by other drivers.

In addition to that, occasionally drivers will go faster (emergency, being late, and so on) and those same slow drivers that occupy each one of the 5 lanes at the same time will amplify the lane splitting, ultimately causing temporary traffic jams.

I never really understood why is this - in Europe we automatically merge to the right and always try to keep the leftest lane available for whoever needs to use it.

Reason for the CA rules is that, in the US, the rightmost lane is where all the entrance and exit ramps are, so you often have people speeding up or slowing down as they enter and exit. Rather than have to do a ton of lane changes to pass people as they merge on, the advice to stay in the middle lane if you just want to stay a constant speed is so you don't have to deal as much with people entering and exiting your lane.

Yes, in that case a driver not understanding the rules of the road (that you can't take the first exit from the inner lane, which is usually clearly signed) could cause an accident. The exact same way turning right from the left lane in a signalized intersection can cause an accident. The question is, what's the damage of an ignorant driver and how fast do people learn? The research indicates that right-of-way incursions in a roundabout result in dramatically fewer injuries than right-of-way incursions at other types of intersections, and the research also indicates that contrary to your belief, drivers actually do learn how to use them.