RC:
... the Cayenne Turbo is a fantastic car but when it comes to throttle response and shifting, there is no substitute to the X5 M. The X5 M beats through the gears like a maniac and throttle response from standstill is almost instant....
... starting with 2011 Cayennes throttle response and shifting have become an instant too vs pre2011 generation Cayennes...
There are no more any delays in gear shifting in a 2011 Cayenne, no throttle response delays anymore. 2011 Cayenne transmission was completely changed. It feels, as a different animal (8speed) vs pre2011 Cayenne transmission ( "full of programming system bugs" 6speed).
2011 Cayenne goes through gear shifts, like "knife goes through butter". Throttle is instant too.
I suggest to repeat your test, RC, (your X5M vs 2011 CayenneTT) but with a better Cayenne driver, maybe, and a Cayenne with some more "post break-in" mileage (more, than 5000km)... and don't forget to engage 2011CayTT two buttons: sport button+PSM off (to take a car off a relaxed driving mode ). Even better suggestion: drive TWO tests with drivers SWITCHED after first test. So YOU, RC, drive 2011CayTT for the second test.
Also try to go for the longer distance and more speed (250-260 km/h maybe).
The 2011 car is really fast and "feels light", I do not expect X5M to run away from 2011 CayTT by two car lengths...may be the opposite as a distance and speed encrease starting 180 km/h upto 250-260 km/h, maybe...
...one more observation...
The more I drive 2011 car the more I notice, that underneath 2011 Cayenne body IS a DIFFERENT car="a little modified Panamera", but not "modified/renewed/refreshed pre2011Cayenne"...PORSCHE AG changed 2011 Cayenne internal body/structure radically!
And for cost savings made it too close to "Panamera w auto transmission"...
...just take a very close look at 2011 Cayenne vs Panamera driveline size/length/height/width/weight/ etc. body size stats and internals look ...