Simple merges strategy are "good enough" in practice.
"We have tried to draw spirals using cartesian coordinates, what we have gets us 90% there, but there are infinities and edge cases involved in getting a perfect spiral. The equations describing them would get so complicated it's just not worth it."
What we have in BitKeeper is the equivalent of polar coordinates... it makes drawing spirals much, much easier ;)
I would be nice if you could give some examples where bk gets the merge right while git doesn't.
One example that bk gets right and git doesn't is precisely the one explained in the article.
I suspect what you'll find is changing the base in this way, while fixing this problem would introduce other problems that occur much more regularly, but I hope I'm wrong.