GitHub's quirks definitely make life much harder than it needs to be, but I've been using `git machete` for months now with great success in my team. The __one__ thing GitHub has that makes it all work is the fact that if you merge the parentmost branch, its immediate child will retarget its base branch.

I think if I had full "control" over my company's SCM workflows I would use a tool that considers a branch as a workspace and every commit in the branch becomes its own PR (personal preference, but in my experience it also motivates people to split changes more), but alas.