alt Hacker NewsAs a northeasterner, I can explain:
In some other places, a turn signal before a lane change is an ask, to which others respond by creating more of a gap than there originally was. Here, it's not an ask but a statement that you've got enough of a gap already so you're going for it. As such, others don't find a need to react at all, which could mean the gap continues shrinking if it was already shrinking prior.
The signaler needs to have anticipated it and not signaled until this problem doesn't exist, in fact it's scary when someone signals despite this problem because the other driver is led to believe they're unseen. When there's already a lot of momentum toward closing the gap, continuing to do so is a more fuel-efficient way out of the blind spot than using the brake pedal.
Aside: turn signals that automatically flash 3 times with no reasonable way to cancel the remaining flashes when you discover a need to abort a lane change exacerbates the aforementioned scare, so I recommend disabling it.
> The signaler needs to have anticipated it and not signaled until this problem doesn't exist
How do you handle an upcoming left turn (assuming right hand driving) during heavy traffic?
It's not the responsibility of the car changing lanes to optimize the fuel economy of the cars behind, but it is the responsibility of the cars behind to not needlessly impede other drivers from getting where they need to go.
> When there's already a lot of momentum toward closing the gap
Does "momentum towards closing the gap" just mean that you're keeping a higher speed than the car in front of you? I don't see any reason you'd do this unless you have another free lane to the left and are planning to pass. If you don't then you're just reducing your margins to the next car for no reward, as you'd have to slow down anyway once the gap is "closed".