In summary, to actually have happened this accident would have had to take:
- an idiot not having a single look at the commits he pushes, plus
- a lawyer forcing him to add a copyright header longer than the rest of the file.
Clearly the type of thing that happens everyday at the git-svn office.
Once again and more seriously: every single limitation of git-svn can quickly be worked around by temporarily (and rarely) switching back to the plain SVN client.