The transmission is adaptive to your driving style. If you cruise
around on the highway, the trans will adapt to slower kick-down
comands. If you drive in stop and go fast paced driving, the trans
will adapt itself to downshift firmer and faster.
The trans usually upshifts to it's highest gear as soon as possible for maximum fuel economy and lower revs. It is fairly common for
a C280 to be in 5th gear at 34 mph. That means, when you hammer the gas, it has to downshift 2 or 3 gears to get the rev's
up and start acceling. Delayed throttle response is a common trait of the new 3 valve engines and the 5 spd auto.
Sorry but it normal situation. The MB engineers have solved this
problem with the new "Speed Shift" tranny on new AMG cars.
The trans is much more sensitive to throttle imputs and downshifts come 60% quicker.
I can only hope this sytem makes it into all the trannys in the future.