Driving habits should be wired into our sub conscious & instinct. I've had a situation where I was accelerating on a highway and the pedal was stuck under the matt (automatic honda). My first instinct was to hit the breaks, alright didn't do much, then I slapped it in neutral and while the engine was screaming at me I was able to pull the matt under and the accelerator was released. I slapped it back into drive & put on my hazards for a few moments while I composed myself (still driving at this point).
Another instance I had was following too closely and the guy in front of me decided to stop at the yellow light. I instantly slammed on my breaks but due to road conditions I rear ended him. Luckily the speed of my reaction minimized any potential injuries, although I still wrote off my car.
Two situations where my instinct saved my butt from a potentially fatal situation.
I did have one instance where I was sitting at a light and I saw a salt dump truck barreling down the road to the left of me incoming into the intersection - he lost control in the snow, figure that one out. I put the car in reverse put because I was so tense it slapped into park (still the automatic Honda). At that point I froze like a deer in headlights. Luckily this behemoth of a vehicle only took out my bumper as he turned int he last minute, but it's an example of where you have enough time to make the correct reaction, but you don't take it because you're just frozen.
For what it's worth, this last situation also preceded the previous two, so maybe it gave me nerves of steel and I'm better equipped to handle intense road situations, but I can see it happen. A side note, I think a manual transmission vehicle is better than automatic for obvious reasons.