I was under the impression that git didn't do well with large files.
Yeah. We used to store PowerDesigner files in git a while back, which are XMLs usually smaller than 100 MB, and that was pretty much a disaster of hour taking clones already. I can't imagine 700 MB working.
Have you considered git LFS, i.e., git Large File Storage?
I've used it to store 20-80GB of files in a repo and it works quite well.
I'm pretty sure that was with LFS. Maybe the issue was Bitbucket? I'm not sure.
Good point - I wonder if the XML really is "diffable" or if it's basically encoded binary data and has to be stored as a blob anyway.