Change behavior of git add --patch on newly added file?

[Emily Shaffer <emilyshaffer@google.com>]

Should 'git add -p <newly-added-file>' do the same thing as 'git add -N
<newly-added-file && git add -p <newly-added-file>'?

To demonstrate:
  git init .
  printf "%s\n" {1..10} >newfile
  git add -p newfile

This outputs "No changes." 'git status' shows that 'newfile' is
untracked.

However, since I want each of my commits to be atomic, I want only lines
1-5 in my first commit. (Or more realistically, maybe I only want
function stubs.)

I *can* do:
  git add -N newfile
  git add -p newfile

But, why doesn't 'git add -p' just do that on its own? At the very
least, "No changes" is a pretty cryptic output - there ARE changes,
right here in my workspace! (I think it means "there isn't a 'newfile' in
the index, so we can't say whether there is a difference between
'newfile' in the index and 'newfile' in your working tree".)

And if I reason to myself, "I can only add --patch a file which is
tracked, so I need to track this file first" and go skimming through the
documentation for "git add", -N doesn't jump out very much:

  -N, --intent-to-add   record only the fact that the path will be added later

or,

  -N, --intent-to-add
      Record only the fact that the path will be added later. An entry for the path is placed in
      the index with no content. This is useful for, among other things, showing the unstaged
      content of such files with git diff and committing them with git commit -a.

Considering that other parts of the add documentation talk about
tracked or untracked files, I personally miss the upshot that we are
tracking a file which was previously untracked with '-N'. (My gut
guess is that while many Git users are familiar with "tracked" or
"untracked" but less Git users are familiar with what it means to "place
in the index".)

Interestingly, in the whole-file deletion case, I *do* get interactive
support....kind of.

  rm trackedfile
  git add -p trackedfile

  diff --git a/trackedfile b/trackedfile
  index f00c965..0000000
  --- a/trackedfile
  +++ /dev/null
  deleted file mode 100644
  @@ -1,10 +0,0 @@
  -1
  -2
  -3
  -4
  -5
  -6
  -7
  -8
  -9
  -10
  (1/1) Stage deletion [y,n,q,a,d,?]? e
  Sorry, cannot edit this hunk


Is there a reason that git add -p can't do whole-file support this way?
While I'm less sure about what I'd like to see for copied files, I do
feel like there's a strong argument for patch adding new or deleted
files.

 - Emily