Hi Junio,
I very much appreciate the feedback and believe I have changed things to match.
To answer your earlier question, the hook doesn't need to support multiple header capitalizations (ie. only Cc is passed). However, it does need to understand that lines beginning with whitespace belong to the previous header. The header information follows the same format as the confirmation given at the end of send-email.
Michael Strawbridge (2):
send-email: refactor header generation functions
send-email: expose header information to git-send-email's
sendemail-validate hook Documentation/githooks.txt | 17 ++++++--
git-send-email.perl | 80 +++++++++++++++++++++++++-------------
t/t9001-send-email.sh | 29 +++++++++++++-
3 files changed, 92 insertions(+), 34 deletions(-)