I had a friend who was driving his girlfriends Toyota (one of those small SUV ones) that had the accelerator stick while getting on the freeway (also in SoCal BTW, along the 101 freeway). It wasn't a drive by wire though, the accelerator cable had frayed at the throttle body preventing it from returning. I am really surprised that did not generate some sort of recall, the car was not that old.
I don't think he was at full throttle, but he was able to keep the speed down with the brakes but they will of course eventually overheat. He managed to get the car over and set it up so he could kill the engine and coast to a stop.
Two things to consider with killing the engine. One, you loose a lot of braking power as your brakes now become non-powered. Two, you have to be careful not to lock the steering! I remember a story of that happening in a Ferrari, the accelerator stuck, he killed the car but locked the steering and ran into a parked car. (I think that may have been a rock star, maybe Sammy Hagar?)
My car stuck at full throttle once during an autocross (had some ill advised throttle shaft seals on the secondary carbs). After making a somewhat spectacular doughnut, I finished the course by turning the ignition on and off. The benefit of simple ignition, no power steering, no power brakes and no locking steering wheel.
This also reminds me of something I feel strongly about with aviation: Learn how (and when) to crash! (or sacrifice the vehicle). I mean come on, there have been quite a few people killed by trying to save some damage to their plane ( maybe cars also). What is more important to you, your plane / car, or your life!?
