-A convenient way to perform this check is to import the tarball as
-described in the following section, using a different value for
-'upstream-tag', and then use git-diff(1) to compare the imported
-tarball to the release tag. If they are the same, you can use
-upstream's tarball instead of running git-deborig(1).
+If, as a user of the upstream source, you usually build from upstream
+tarball releases, rather than upstream git tags, you will sometimes
+find that the git tree doesn't contain everything that is in the
+tarball.
+
+Additional build steps may be needed. For example, you may need your
+I<debian/rules> to run autotools.
+
+You can compare the upstream tarball release, and upstream git tag,
+within git, by importing the tarball into git as described in the
+next section, using a different value for 'upstream-tag', and then
+using git-diff(1) to compare the imported tarball to the release tag.
+
+=back
+
+=head3 Using untagged upstream commits
+
+=over 4
+
+Sometimes upstream does not tag their releases, or you want to package
+an unreleased git snapshot. In such a case you can create your own
+upstream release tag, of the form B<upstream/>I<ver>, where I<ver> is
+the upstream version you plan to put in I<debian/changelog>. The
+B<upstream/> prefix ensures that your tag will not clash with any tags
+upstream later creates.
+
+For example, suppose that the latest upstream release is 1.2.2 and you
+want to package git commit ab34c21 which was made on 2013-12-11. A
+common convention is to use the upstream version number
+1.2.2+git20131211.ab34c21 and so you could use
+
+=over 4
+
+ % git tag -s upstream/1.2.2+git20131211.ab34c21 ab34c21
+
+=back
+
+to obtain a release tag, and then proceed as above.