> If commits were stored as diffs, then Git would have to rebuild a tree of the very first commit, then replay every single diff Well, it would usually be more

> If commits were stored as diffs, then Git would have to rebuild a tree of the very first commit, then replay every single diff Well, it would usually be more efficient to figure out where the current checked out branch differ from the branch that is checked out, and then unapply and apply diffs as needed.