I haven't read every post, but the 5AT does not upshift in manual mode, it will keep bouncing off the rev limiter. I drag race my Z and know it will do 100+ in 3rd gear as that is what I was turning in the 1/4 still in 3rd. I do burnouts in 1st gear and thank God it doesn't shift by itself. My 5AT is stock and shifts quickly enough to break the tires loose in 2nd and 3rd gear.

 

so it accelerates much faster if i keep the foot on the gas while shifting?

 

That's what i do. It is to the floor all the way through the 1/4 mile and while I shift. The ECU seems to pick up how you drive. If you drive conservativly it seems to shift easier. It doesn't seem to take long to get aggresive though. I wind it up at WOT and go through the gears a few times on my way to the strip to make sure it is in the aggresive mod. shift about 200-300 rpm's before redline as the rpms go up that much between shifts and you don't want to hit the rev limiter.

 

The 5AT is a real-time learning transmission. It will adapt to the driver's driving style and environment. Drive it aggressively and the transmission will react aggressively. Drive it like a granny and that is how it reacts.

The 5AT and just about all tiptronic style transmissions should be shifted at constant or accelerating throttle. It doesn't need you to help it shift, you'll just cause driver error. Just tell it when to shift and let it do it's thing.

For racing, follow Fowlman's suggestion.