Mildly Infuriating

I think this advice made more sense when the majority drove reasonably-sized vehicles rather than the huge trucks and SUVs that pollute our roads now (at least in North America).

I wouldn't be surprised if this bit of advice contributes to the problem in OP.

In case of armed road rage, remember that your car is a weapon. It's self-defense if a gun is drawn on you.

Yup, I see this shit all the time. "The sooner I stop the faster I can stare at my fucking phone!" It's one thing I wish was actually policed, cause these people are a menace. It's one thing to risk your own life, but those dumb asses are making it dangerous for all of us around them. Throw in two or more and baby you've got a stew going.

I usually flash my high beams first as a more gentle “look up” and then do the horn if they don’t notice that one

Once the light turns green I give a solid three count then I honk

In Ottawa it's a customary 4 picoseconds.

so with modern hood heights, that's... 30 meters?

I still hear my driving instructor saying this, 30 years ago. Thanks. :D

I don't know... People have wildly different positions in a car and this easily fluctuates for a few car lengths. Then again, people in general suck at estimating distances.

I agree it's highly unlikely. However, I've been rear-ended once, and my car got pushed forward the space of at least another car and a half, in spite of my panicked reflex of pressing the brakes as it happened. I didn't crash into anything because I was first on the lane, I got pushed into the intersection.

So yes, you can get rear-ended and the gap in front of you will save you in money and insurance claims bs time if you don't hit anyone in front as well as a result. It will make little difference regarding your ability to switch lanes though.

In saying that, I don't leave this massive space in front of me. I stick to the "see the next car's tyres" rule and if traffic is really packed (as during rush hour, when everyone crawls start stop) I sometimes reduce it to curb parking distance.

I'd just be like "my bad dude" and pull a little bit closer after that. What a weenie.

That works for small cars with hoods that slope to the ground like sedans and station wagons. It is outdated and useless advice for anyone in an SUV, pickup, or the vast majority of vehicles on the road today in the US.

It should be far enough back to be able to turn and move out if the car in front of you stalls, which should be easy to estimate for anyone who can parallel park.

Everyone should be able to parallel park, it is part of the driving test.

Or worse, people who stop just past it, but not far enough to get the car behind it to actually touch the sensor

The correct answer

There sometimes are induction loops under the street for this purpose: https://en.m.wikipedia.org/wiki/Induction_loop

In Germany almost every traffic light has them nowadays. It can sometimes be annoying when you're riding a bike made of carbon. But usually my phone and laptop seem to be enough to trigger them.