Insert a commit before the root commit in Git?

I've asked before about how to squash the first two commits in a git repository. While the solutions are rather interesting and not really as mind-warping as some other things in git, they're still a bit of the proverbial bag of hurt if you need to repeat the procedure many times along the development of your project. So, I'd rather go through pain only once, and then be able to forever use the st

[ysugitani]

役に立ったメモ - 最初のコミットの前に空コミットを後から入れる

[aereal]

なるほど git rebase --onto --root