Fair enough, but as far as I know not a valid point in this specific case.
>>Braking is a software function
Yes, but a completely separated system. The odds of both software systems failing simultaneously is getting in the hash collisions domain...
>>most Americans drive automatic (software) transmissions.
Again a seperate system, and you still have a neutral position.
Are you sure? It seems sensible to me that accelerator inputs would factor heavily into the braking system, so it seems very sensible to me that an unexpected condition in one could translate over to the other - as the article noted the only way to undo one unexpected acceleration condition was to completely remove your foot from the brake pedal. Sounds like cross-over to me...
>you still have a neutral position.
... which is likely just a software input to the transmission computer.
In all likelihood the only non-electronic failsafe is the handbrake, which I still think is a direct mechanical connection in almost all cars.
Not on my Nissan Leaf. The brake lever is a switch that turns what I assume (based on the noise) is a small motor to engage the rear brakes. As far as I can tell, everything is electronically controlled. Brakes, accelerator, "ignition", "transmission" (both in quotes because the Leaf really has neither), parking brake. If there's a firmware failure, there's not a mechanically-operated fail safe to save me.
It isn't, really, in a lot of newer cars. You have a brake override system [1] that can reduce the power output of the engine by various means.
[1]: http://auto.howstuffworks.com/car-driving-safety/safety-regu...