Not entirely sure it's relevant to this discussion.
However, a while ago, I read that the reason for the the auto v manual came down to emissions. A manual at most may have 6, or 7 forward gears, whereas as auto may have up to 9. If an engine is in 9th gear (auto) as opposed to 6th (manual) at the emissions test level chances are it's revving a lot lower in a auto than a manual.
Also, from a performance point of view, a DCT auto can change much quicker than the squidgy human bag of blob behind the wheel