Oh! I made a mistake. You do not have to delete or use the special config flag if you use --force for your push. I wondered why I remembered doing this on side branches. With --force, we do not have to do this. Also, I think you need to make sure you have -u on this kind of push so that you maintain your tracking connection, but I am not 100% positive.

Don't do this:

    git push origin :master

Do this:

    git push -u --force origin master:master