### Please describe the problem.

Playing with the new fancy "export" feature.  Thanks again!

Somehow I see now commits in the git-annex branch in the quick succession establishing and then killing a "graft".
Are they really needed/used by annex or could have been squashed/avoided?

some details of the recent history of commands and how git-annex branch looks like are listed below


### What version of git-annex are you using? On what operating system?

6.20171018+gitgbb20b1ed3-1~ndall+1

### Please provide any additional information below.

[[!format sh """

14883  tree /tmp/test-directory-export -a
14887  git annex info
14888  git annex export --to=directory-export
14889  git annex export
14890  git annex export --tracking master --to public-s3
14891  git annex export --tracking master --to directory-export
14892  git annex export
14893  git annex export --to directory-export
14894  git annex export
14896  git annex sync --content
14898  git log --stat git-annex


$> git lg --stat git-annex | head -n 30
* 4a03be8 - (git-annex) update (4 minutes ago) [Yaroslav Halchenko]| 
|  export.log | 2 +-
|  1 file changed, 1 insertion(+), 1 deletion(-)

* b23ae9d - graft cleanup (4 minutes ago) [Yaroslav Halchenko]| 
|  export.tree/.datalad/.gitattributes | 3 ---
|  export.tree/.datalad/config         | 2 --
|  export.tree/.gitattributes          | 1 -
|  export.tree/123                     | 1 -
|  export.tree/sub/dir/11              | 1 -
|  5 files changed, 8 deletions(-)

* 6a0bc5f - graft (4 minutes ago) [Yaroslav Halchenko]| 
|  export.tree/.datalad/.gitattributes | 3 +++
|  export.tree/.datalad/config         | 2 ++
|  export.tree/.gitattributes          | 1 +
|  export.tree/123                     | 1 +
|  export.tree/sub/dir/11              | 1 +
|  5 files changed, 8 insertions(+)

* 919e345 - update (5 minutes ago) [Yaroslav Halchenko]| 
|  export.log | 2 +-
|  1 file changed, 1 insertion(+), 1 deletion(-)

"""]]

[[!meta author=yoh]]

> Seems we're ok, so [[done]] --[[Joey]]
