My friend... this is something most of us has experienced including G37 owners:
Loss in acceleration + throttle response ??
Gas Pedal Delay
I wish the car was a bit more eager to accelerate in 1st like the 350Z. I know what you mean, though, it does the same with VDC off. It's worse when oil temps are over 200F.
It happens to me every once in awhile as if throttles refuse to open all the way, and I can't even get boost to build up past 3k!