I have an explanation for you- your car is not an automatic transmission. It's a DCT, so you had clutches engaged when you were going fast on that hill. That's how it started- just like a manual transmission vehicle that was shut off with the key, it would decelerate, but if you turned the key back on- the engine would fire right up. However, the transmission has to be turning fast enough to turn the engine fast enough to fire. At 5 mph in whatever gear you were in, it wasn't enough.
Since you can recreate it, and you should not be able to turn your key off while the car is driving, then you should go see your dealer, and recreate it for the service manager. That's the important thing for taking a car in to be repaired- you must be able to recreate the problem, if you can't, then it's not a problem. Things happen sometimes, weird things, outer limits, twilight zone weird, and those things never happen again- without any explanation.
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Originally Posted by the user formerly known as ZX3_Chick
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