Give me a file that was slow and lets see how it is in BitKeeper.  I bet you&#x27;ll be impressed.<p>50K lines is not even 3x bigger than the file I mentioned.  Which we check out in 20 milliseconds.<p>As for optimizing blame, you are missing the point, it&#x27;s not blame, it&#x27;s merge, it&#x27;s copy by reference rather than copy by value.