You have to do something (button press or loud pedal) to get the car moving again once it comes to full stop, so you can make a judgement call when is prudent to move off. The issue with DCT boxes is the transition period, aka clutch slip. Same as a manual, because DCTs are really automated manual transmissions. So, if you think you would need to slip the clutch in a manual, the DCT would likely need to do the same. In those cases don't move off yet. The general idea is to not crawl like most people tend to do coming up to the light and use your auto hold. I found myself while driving the FD manual in stop-start traffic to work out how to release the clutch quick and crawl on idle in first gear. Think of it like that with the DCT and you should be ok. The DCT will handle clutch slip and the related temperature increase but is not recommended to do this for long or on a regular bases. Like manual clutches, it will wear out.