> You probably didn't look very closely at the help page.

  $ hg help commit
  hg commit [OPTION]... [FILE]...
  [snip]

  commit the specified files or all outstanding changes
  [snip]
   -i --interactive         use interactive mode

Yup, it sure does explain that using interactive mode would select individual hunks, sorry for my "if you know you know" comprehension failure, especially in light of the absolutely orthogonal context of that word used further down the help page you allege I did not read:

   -y --noninteractive    do not prompt, automatically pick the first choice for
                          all prompts

> the user experience of `hg split` exceeds anything you can do with git commands

And yet:

  $ hg split --help
  hg: unknown command 'split'
  'split' is provided by the following extension:

      split         command to split a changeset into smaller ones
                    (EXPERIMENTAL)

without saying what makes it experimental - is that "lose work" kind of experimental?