Jim Henderson wrote:
> 
> Well, I've only got something like 20 years of experience driving during 
> winters in Minnesota and Utah to call on.  

I only have 10 in Finland :-). Honestly, I have no idea what kind of
winters there is at Utah or Minnesota, but I assume that means there's
snow and ice available enough.

> It's been my experience that 
> it is generally more effective to downshift and let the engine do the 
> work.  

How could it be? In both styles the negative acceleration is applied to
the ground via tires and tire/ground -layer being the weakest part -
with downshifting most cars do it practically via 1 wheel, almost no car
makes it via 4 wheel (which would mean 4WD with completely locked
differentials), while brakes are applied via all 4 wheels. Breaking with
the engine is of course more economical

> Unless you know with relative precision how slippery it is, 
> tapping the breaks can be a bad prospect.

There might be a language wall here - I'd consider tapping as a slight
touch and hitting the brakes as a 'do-not-do' -movement on ice.

> I've managed to put two cars in the ditch in 20 years.  One from 
> overcorrecting a spin, and one for not slowing down enough because some 
> jackass was tailgating me.  I've never managed to put my car in the ditch 
> by stepping on the brakes, because I was taught not to do that and I 
> don't. <shrug>  I can't argue with what works for me.

We have the same ratio, I've put one in 10 years :). That was due to
lifting the gas pedal while coming back to my lane after overtaking
another car. And well, that was actually no ditch AFAIK, while the same
car is still mine and registered (just now out of the traffic, though -
it's my summer toy).

And I'm not saying that braking with the engine doesn't work - I'm
saying that braking with the brakes works too, it just needs to be done
carefully.

> Yes, that will also work, but yes, it is dependent on knowing the 
> condition of your tires.  I think we both can agree that there is a high 
> degree of situational awareness called for.

*Everything* while driving on ice is dependent on knowing the condition
of tires, more or less. As pointed out, RWD can give you a spin (or try
it) with downshifting, if the road is too slippery. It's always
necessary to know what kind of tires you're driving on and what's their
condition. What I ment is that to test the possibilities to brake with
accelerating you'll need to know the ratio of acceleration traction and
braking traction of your tires. Eg. I once had tires (Kleber Kapnor 4
185/65/15) which were catastrophic when accelerating, but pretty good
when turning and braking.

> Yes, agreed - the more you can practice in a safe environment, the better 
> prepared you'll be.  :-)

And the more fun you'll have (while practicing, of course), so it's a
win-win situation :-).

> Jim

-Aero

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