I fixed up the manpage quite a bit, and I believe it's acceptable now. I looked for inspiration in some section 5 manpages to see about adding one for the makefile format, but I haven't been able to find a good example. So, I've just pointed to the README.txt and EXAMPLE.make files from within the manpage. I'm not sure that this is kosher, but it seems a lot easier than trying to keep two sets of docs (in very different formats) in sync.
I signed it with my gpg key this time during `dpkg-buildpackage`, and Lintian continues not to complain about anything. I've been including the various generated files, along with the orig.tar.gz, but I'm not sure this is necessary. As usual, I'm pushing my updates to�
https://github.com/ergonlogic/drush-make.
As far as I can tell, this package is ready to go. So I'll probably need feedback from someone with some actual experience at this, if I'm going to be able to improve it any further.