Based on the documentation I have, there is not much you can do to automate your pipeline creation. I am hoping the documentation isn't including a lot of the functionality.
In particular, I am hoping that I can iterate through pipelines in a group to duplicate and create new pipelines in a new group (for a branch) that include the following:
pipelines as materials
The documentation does show how you can create the new pipeline group and also how to add the SCM material but according to the documentation that is all you can do.
I saw that someone created a python script by reverse engineering your UI to do some of what I am talking about, but that was over a year ago and I wanted a Thoughtworks supported method so I don't have to chase my tail every time something changes.
Also, if there was a part of the API that gathers the information from existing pipelines/groups so the branch pipelines can be made from those that would be helpful.