There's a very basic problem here that no one seems to be getting. Drivers claim that their cars accelerate even though they push hard on the brake pedal. That's not possible. The brakes are more powerful than the engine. Always. Because it's so much easier and cheaper (both initially and liability-wise) to make powerful brakes than a powerful engine. The brakes win. Every time. No exceptions. You can prove this to yourself by going to a deserted road and flooring the gas pedal. Hold it down, then use your left foot to step on the brake. You can easily bring the car to a dead stop, even with your gas pedal mashed to the floor. Even if you're driving the most over-powered performance car on the road. (If it's a manual transmission, let up around 2000 rpm or you'll damage the engine.)
There is no connection, mechanical, electronic or via software, between the engine management system and the braking system. A failure relating to the gas pedal cannot in any way affect the brakes. Even if all the electronics go completely nuts, the brakes still default to a simple, independent hydraulic system.
This whole story is hogwash. It's the Audi 5000 all over again. Everyone went crazy over how the demonic "unintended acceleration" was going to kill us all. The final conclusion? People were stepping on the wrong pedal.
This is not a technological problem. It's a human factors problem. Still a problem that needs to be addressed, but can we please shut up the science-challenged Chicken Littles so we can address it?