SubmittingPatches: use of older maintenance tracks is an exception

While we could technically fix each and every bug on top of the
commit that introduced it, it is not necessarily practical.  For
trivial and low-value bugfixes, it often is simpler and sufficient
to just fix it in the current maintenance track, leaving the bug
unfixed in the older maintenance tracks.

Demote the "use older maintenance track to fix old bugs" as a side
note, and explain that the choice is used only in exceptional cases.

Signed-off-by: Junio C Hamano <[email protected]>

Author: gitster

Documentation/SubmittingPatches

@@ -46,15 +46,22 @@ latest HEAD commit of `maint` or `master` based on the following cases:
 * If you are fixing bugs in the released version, use `maint` as the
   starting point (which may mean you have to fix things without using
   new API features on the cutting edge that recently appeared in
-  `master` but were not available in the released version). If the bug
-  exists in an older version (e.g., commit `X` introduced the bug, and
-  `git describe --contains X` says `v2.30.0-rc2-gXXXXXX` has it), then
-  use the tip of the maintenance branch for the 2.30.x versions in the
-  `maint-2.30` branch in https://github.com/gitster/git[the maintainer's
-  repo].
+  `master` but were not available in the released version).
 
 * Otherwise (such as if you are adding new features) use `master`.
 
+
+NOTE: In exceptional cases, a bug that was introduced in an old
+version may have to be fixed for users of releases that are much older
+than the recent releases.  `git describe --contains X` may describe
+`X` as `v2.30.0-rc2-gXXXXXX` for the commit `X` that introduced the
+bug, and the bug may be so high-impact that we may need to issue a new
+maintenance release for Git 2.30.x series, when "Git 2.41.0" is the
+current release.  In such a case, you may want to use the tip of the
+maintenance branch for the 2.30.x series, which may be available in the
+`maint-2.30` branch in https://github.com/gitster/git[the maintainer's
+"broken out" repo].
+
 This also means that `next` or `seen` are inappropriate starting points
 for your work, if you want your work to have a realistic chance of
 graduating to `master`.  They are simply not designed to be used as a