[kazinator]

Even public history can be rewritten, and it's not too bad to deal with. For several months, earlier this year, I was battling some tough bugs in a kernel USB driver, along with a few other developers. I set up a "wild repository" (not an official repository, but one for experimental changes---though public in the sense of being shared). I rewrote the testing branch regularly. I even adopted a scheme, whereby I would rename a branch through the names "name.1" and "name.2" (deleting the old name.2), similarly to rotating logs. I'd send out a "heads up" e-mail whenever I did this.

A rewritten branch isn't hard to pick up. Git tells you that the history has diverged (N commits here, M over there). If none of the local history is yours, you can just throw it away with a "git reset --hard <origin>/<branch>". Or else you can rebase those changes which are yours.

It's only bad to rewrite "really public" branches that are distributed to the world. Even then, it can be okay to clean up some oops: like seconds after pushing a release, some last minute change needs to be made (typo in the release notes file or whatever).