alt Hacker NewsFwiw, in plain git, there's 2 dates associated with commits. The author date tells when the content was authored, and doesn't change with rebase. Only the commit date changes. So the correct metadata is already there, and even more precise. It can tell you both when it was authored, and when it's history was last changed.
The author date was when it was introduced to Parliament, the commit date is the date of Royal Assent. Ditto with the date a referendum was called versus when its results were certified, etc.