Currently, format-patch puts base-commit and prerequisite-patch-id
information below the patch, and below the email signature. Most mail
clients automatically trim everything below the signature marker as
unimportant when quoting a mail for a reply, which would make it
difficult for someone to reply, quote the base-commit, and say something
like "I don't have this commit, where did it come from?" or "Can you
please rebase this on ...".
Might it make sense to move this information adjacent to the diffstat,
instead? Or, at least, above the email signature?