adding the branch at commit time is possible, but doesn't match the working style, to start with a branch! The branch itself is an important step in this working style. We document the fact, that there is active development by starting the branch - without any changes!

OK, we can do a commt with branch and force. This would be a proper replacement for the branch new command. But in this case, it should be mentioned in the documentation - maybe as a table of command replacements:

  *  scm (example: <kbd>CVS</kbd>)
  *  scm command(<kbd>cvs tag -b branch</kbd>)
  *  fossil replacement(<kbd>fossil commit -m "start new branch" -b branch -f</kbd>)