Proper plumbing for porcelain gpg formats on git show?

I can't agree that 

COMMITID=ef8df950c8d16dace62e55d18b26617b1268f1bc; \
 git cat-file $COMMITID -p |\
 sed -e '/^ /{H;$!d;}; x;/^gpgsig /!d; s/^gpgsig//;' |\
 cut -c 2- |\
 gpg --list-packets --textmode |\
 sed '/keyid/!d; s/.*keyid \([0-9A-F]\{16\}\).*/\1/I'

is the way to go, when 

COMMITID=ef8df950c8d16dace62e55d18b26617b1268f1bc; \
 git log $COMMITID --pretty=format:%GK -n 1

and

COMMITID=ef8df950c8d16dace62e55d18b26617b1268f1bc; \
 git show $COMMITID --pretty=format:%GK -s

do the same thing.

Is there a way to properly extract the GPG signature object, such that GPG operations may be done on it?

Are the git log formats safe to use in scripts (asking because it was said not to use at http://git.661346.n2.nabble.com/show-pretty-B-without-a-diff-td5852061.html#a5853270)?

If git log with format specifiers is safe to use, would there be interest in accepting a patch for 

%Gs - the raw GPG text from the commit %Gf - the key fingerprint

-Jason

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- Jason Pyeron                      PD Inc. http://www.pdinc.us -
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