I am still not 100% sure if I understand what you want.
Another option thrown into the ring, without being sure if that would
work for you:
You could have one branch with and one without README.rst and have one
rebase on the other automagically.
As an aside: If you have more than one instance of ~/README.rst and
vcsh/Git are aware of this, they will all consider what the other
repos do as "changes" and thus battle each other unless you take
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