not sure that it works when in Manual mode but i have never tried, it basicly does the task of down shifting for you... when you are in automatic mode, it will shift to the lowest possible gear for maximum power, i have a feeling that it would do the same in manual mode as well but like i said i have never tired it, usually pretty high in the powerband already. But i have learned that the throttle positioning is pretty good for this car, always seems ready to put the motor in the best position for your need.
Ohhhh ... u know what? I believe I've experienced that already! There have been times when the car has revved in low gear for a longer time than I like, so I'll hit the pedal and she'll 'lurch' forward and then upshift. I'm not one to tap my brakes whenever someone in front of me does (I'm not that close), so I'll just decelerate and she'll downshift. However, when I'm in stop-&-go traffic sometimes, that's what happens.