I had this same issue in my 2010 VW CC. Everything I read seemed to attribute it to the DSG transmission. That lag/hesitation has been one of the main reasons I just couldn't pull the trigger to move to an A4.One of the things I hated about my 2012 A4. Can't believe it hasn't been resolved.
My impression of my A4.
[Mash the pedal.]
A4: Oh, do you want to go?
A4: Are you sure?
Me: Yes! For the love of God, go!
A4: OK. If you are really sure.
[Finally starts moving.]