Josef Weidendorfer [off-list ref] writes:
But not supporting this in a first step should be no problem, as
you always can do "git pull somewhere that-head" directly.
That defeats the point of .git/remotes/ setup, and I suspect is
unacceptable to people who pull from a given branch of a given
repository repeatedly without ever tracking it. Think of the
maintainer pulling from subsystem maintainers.