I spend about 5 months every year driving in snow and ice - this is the first I'm hearing about dropping it into neutral. Can you elaborate on when that would be appropriate? Obviously you shouldn't be slamming on the brakes, but they do work fine in snow and ice. I don't see how rolling into things while not in gear is an improvement?
I think the OP means in a manual transmission. Auto will decouple at low speeds / engine braking won't be as severe. In a manual car, in 1st gear, I could possibly see it.
As someone who grew up BEFORE ABS, drove in the winter (in Canada), including first winter owning my own car with sport tires because I couldn't afford winter tires, spun / slid a few times even with top-of-the-line winter tires, etc.
ABS is a game changer in the snow. I used to go to an empty parking lot every winter during early snowfalls to play around and skid, start/stop, etc. Even EARLY ABS ('94 VW) means that 98% of the time (IMHO), the answer even in snow/ice is "slam on the brakes". Sure, you might have a few percent longer stopping distance than an expert who can do threshold braking - are you an expert? And the fact that you don't lose control of the steering is a huge advantage.
I remember being taught the neutral trick for emergency braking back in the 90's, and it had nothing to do with traction in poor conditions. It was simply to remove any engine power that might extend your braking distance. It's definitely bad advice in any modern car.
They mean go into neutral and lightly brake. In a 2WD car, the braking force applies more strongly to the non-powered wheels. Since those were traditionally the back wheels, this meant when going down a hill the front wheels would have more traction. Those are also your steering wheels, which means them locking up is bad. Again, this is the sort of advice that is germane in highly restricted environments which become folk knowledge and later mis applied by humans in ways that reduce safety.
(You also only get into this scenario when your stopping distance is shorter than your reaction time and perception length. Something automated drivers can manage better than humans.)
I think it's often about when you're on rural single lane roads and perfectly bad ice/snow/slush conditions where you need to keep your speed very low, and sometimes even very moderate braking can cause your vehicle to veer off the road and into a snow bank, not necessarily the need to avoid something in front of you
When you let off the throttle your wheels start driving the engine and slowing you down. In snow/ice that engine breaking alone can be more braking force than is safe and so you go into a skid. Shifting to neutral removes engine braking and allows for more controlled slowing down.
When it's those conditions though I just use a light touch on the throttle to make wheel speed match ground speed, a lot of easier than trying to shift in and out of neutral.
If you are in a situation where your car is sliding, like down a slick hill. You dont hit breaks, you put the car into neutral and steer into the way your car is sliding to try and keep the car on the road.