Seems that if you have DSG then hill starts and stops are not an issue all works as you expect. What isn't clear is how you could park on a hill.
If you are close to other cars you don't want to lurch forward or backward into them, with a manual I would be rolling the car back and controlling with the foot brake, then going forward and controlling with the clutch in order to edge in/out of a tight space.
With the auto hold it seems like best case you've got to be really careful. Stopping the car with the foot brake is fine, then you put the DSG in 1 or R... now the tricky bit, you need to accelerate to disengage the brake, but then immediately stop accelerating. I think reverse would be worse because you have to control using the foot brake against the DSG yet not bring the car to a full stop or the parking brake will engage and you'll need to accelerate again (only now the space is smaller!). In a manual I would be edging the car forward or back a few inches at a time, but with auto hold I don't see how this is really possible. It expects you to be smoothly drawing away at speed...
Perhaps I should have ordered park assist.