[Binny]

I found the same when I got my Mondeo TDCi a few months ago. Once I had a think about how the powershift works and adjusted how I drove a I almost never experience it.
When you are stationary at the lights with the brakes on the car is basically holding the clutch all the way in for you. If you then jump straight from the brakes to the throttle it needs to "catch up" and let the clutch out without being too abrupt and stalling or sending you launching forward into the car in front.
If you are able to anticipate when the lights are going to go green, or when the cars in front of you are going to start moving take your foot off the brake without using the throttle yet. You will feel the car ease out the clutch until it reaches the friction point and will start to creep forward slightly like a conventional auto does. It only takes a second or so. Then you can give it as much or as little throttle as appropriate and it will take off accordingly, no jerking, no thumps no dramas.
Well it works for me anyway. You may already know this buts its worth a go if you didn't.