@bored@work:
Actually (almost) every car has a dual brake system. The master brake cylinder consists of two seperate cylinders which feed the brake calipers on different wheels. So worst case you'll have half the braking capacity. I wouldn't call that a single point of failure.
Braking on the engine is not to be underestimated. When driving downhill its the only viable option.
A single point of failure is that, a point, not the whole system. When a system has a single point of failure it means that when that single point fails the whole system fails. Redundancy of other system components don't help if the system depends on that single point.
The pedal as such is a single point of failure. You have no alternative to invoke and control full breaking power. If the pedal breaks, if it got stuck, if it fails in any way, you are screwed. You can no longer control your full breaking system.
The accelerator is just a pedal on a potmeter with a spring.
Like with the break pedal we can agree there is only one, and its proper function is relevant for safety and it is a single point of failure. Something this Barr dude claims
Anyone working with safe systems knows that single points of failure are to be avoided at almost any cost,
So now show me where in a car this single point of failure "is avoided at almost any cost"? Where is the redundant accelerator pedal or redundant break pedal?
What I want to point out is that this Barr dude was hired by the plaintiffs to support their case. He is not neutral, and of course he spun everything he legally could in the way the plaintiffs needed it. This "Anyone working with safety systems ..." is a statement where he spins the truth. And he manged to convince the judge/jury more than the defense managed. Not everything he says is absolutely true, and the article in EDN is public relations work to drum up more business for him (or, if you believe in a conspiracy against Toyota, to further damage Toyota).
You should also take into account that US courts love to sit with the plaintiffs when they are ordinary citizens and the defendant is a big corporation. Especially a foreign corporation.
Of course, the not so great, maybe even sad state of the Toyota code and their omissions helped that Barr dude to argue in favor of those who paid him. It doesn't mean he found out the absolute truth.