[kevin-oconnell]

If using git as the backend were an option, this problem would be hundreds of times easier to solve. Legal documents have a lot of complex formatting and include elements like tables, images, and footnotes. The diff function needs to handle all this, so it needs to be custom built from the ground up.

[pitaj]

If git is used as just a backend, all of those elements could feasibly be extracted into a textual representation, which git can diff and merge and such, but those diffs and merges are presented to the user graphically in a style they recognize.