Update ballot.md

diff --git a/914897_merged_usr/ballot.md b/914897_merged_usr/ballot.md
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--- a/914897_merged_usr/ballot.md
+++ b/914897_merged_usr/ballot.md
@@ -2,6 +2,8 @@
 
 === DRAFT Resolution ===
 
+## What is "merged `/usr`"
+
 "Merged `/usr`" describes a possible future standard directories scheme in which the `/{bin,sbin,lib}/` directories have been made superfluous, either through making these symlinks to their `/usr` equivalents (/usr/{bin,sbin,lib}) or by removing them entirely.
 The motivation to get Debian systems to converge towards such a scheme is vastly documented elsewhere ([FDO's TheCaseForTheUsrMerge][0], [wiki.d.o UsrMerge][1]) but can be summarized as the following points:
 
@@ -15,11 +17,13 @@ The motivation to get Debian systems to converge towards such a scheme is vastly
 The arguments against moving the base directories' scheme towards "merged `/usr`" are as follows:
 
 * there's no gain in disrupting something that is not inherently broken;
-* `/{bin,sbin,lib}/` → `/usr/{bin,sbin,lib}/` symlinks create confusing views of the system (`/bin/cat` and /usr/bin/cat are the same file), and dpkg doesn't support this situation cleanly [#134758] [https://bugs.debian.org/134758].
+* `/{bin,sbin,lib}/` → `/usr/{bin,sbin,lib}/` symlinks create confusing views of the system (`/bin/cat` and /usr/bin/cat are the same file), and dpkg doesn't support this situation cleanly [#134758](https://bugs.debian.org/134758).
 
 [0]: https://www.freedesktop.org/wiki/Software/systemd/TheCaseForTheUsrMerge/
 [1]: https://wiki.debian.org/UsrMerge
 
+## "merged `/usr`" in Debian
+
 In Debian buster, the current testing suite, "merged `/usr`" is only considered for implementation with symlinks (there are no proposals for simply dropping `/{bin,sbin,lib}`) and is implemented in two distinct ways:
 
 * existing hosts can be made to have a "merged `/usr`" by installing the [usrmerge][2] package;
@@ -29,21 +33,37 @@ The usrmerge package contains a `/usr/lib/convert-usrmerge` perl executable that
 
 [2]: https://tracker.debian.org/pkg/usrmerge
 
+## Issues from "merged `/usr`"
+
 Since the default change in debootstrap 1.0.102, some issues have arisen. Due to the fact that some buster/sid hosts have the "merged `/usr`" symlinks in place, it has been observed that some binary packages carried some traces of these differences (notably official packages built on Debian buildd hosts which had been resetup). Some such differences can actually render the built packages unuseable on non-"merged `/usr`" systems. For example, if `cat` is detected at build-time in `/usr/bin/cat` (where coreutils ships `/bin/cat`), a binary hardcoding that path will try to use `/usr/bin/cat` after installation, but that path doesn't exist in non-"merged `/usr`" systems. In order to mitigate this, debootstrap has been modified to let its "buildd" variant be non-"merged `/usr`", the Debian buildds have been resetup and the affected packages rebuilt.
 
-The lesson here is that with the existance of (any of) the usrmerge and the debootstrap default change, "merged `/usr`" Debian systems exist already, and that packages built on hosts with such directory schemes can _potentially_ be broken on non-"merged `/usr`" systems. At this point, the two variants have to be supported, at least as installation targets of Debian packages.
+The lesson here is that with the existance of (any of) the usrmerge and the debootstrap default change, "merged `/usr`" Debian systems exist already, and that packages built on hosts with such directory schemes can _potentially_ be broken on non-"merged `/usr`" systems. At this point, the two variants have to be supported, at least as installation targets of Debian packages. The fact that packages built on "merged `/usr`" systems are
 
 Two initiatives are worth mentioning at this point:
-* [a patch](https://lists.debian.org/20181202212535.GC11687@gaara.hadrons.org) has been proposed for dpkg to mark packages built on "merged `/usr`" with a `Build-Tainted-By: merged-usr-via-symlinks`;
-* the reproducible builds team has added a "merged `/usr`" variation to their setup, and have then [tagged](https://tests.reproducible-builds.org/debian/issues/unstable/paths_vary_due_to_usrmerge_issue.html) the Debian packages from unstable which had differences due to "merged `/usr`". It seems that ~61 packages were affected by differing builds; 32 from these have been fixed in unstable already.
+* [a patch][https://lists.debian.org/20181202212535.GC11687@gaara.hadrons.org] has been proposed for dpkg-buildpackage to mark packages built on "merged `/usr`" hosts with a `Build-Tainted-By: merged-usr-via-symlinks`;
+* the reproducible builds team has added a "merged `/usr`" variation to their setup, and have then [tagged][https://tests.reproducible-builds.org/debian/issues/unstable/paths_vary_due_to_usrmerge_issue.html] the Debian packages from unstable which had differences due to "merged `/usr`". It seems that ~61 packages were affected by differing builds; 32 from these have been fixed in unstable already.
+
+## The long-term desireable situation
+
+TODO: prose the ideas below, I haven't had enough time.
+
+Given that hosts with different top-level directory schemes already exist; there are various ways forward.
+* flag-day to get all hosts on "merged `/usr`", trough a base-files version; probably in buster+1 (bullseye)
+* disallow "merged `/usr`", let users who ran `usrmerge` on their own
+* let Debian converge to a situation where non-"merged `/usr`" Debian hosts are equivalent to symlinked "merged `/usr`" hosts; do this through upgrading all packages shipping files outside of /usr (but exceptions) to stop doing this. Could be achieved by setting policy for buster+1 (should) and buster+2 (must), or maybe even shorter. This would make the symlink "shortcut" migration redundant.
+* support both "merged `/usr`" and non-"merged `/usr`" systems forever: this implies that our packaging tools need to either support countering effects of "merged `/usr`" (e.g. through manipulating PATH for builds to detect files only in their .deb paths) or identifying tainted packages, and letting installing users decide (warn or error out at install time).
+
+Given the repro build tests, it does not seem impossible to enforce that official Debian packages support being built on either "merged `/usr`" or non-"merged `/usr`" systems.
+
+It's bizarre to have official buildds be non-"merged `/usr`" while user hosts will converge to be more and more "merged `/usr`".
+
+## For buster
+
 
-## Describe what is the desired situation
 
-## Describe ways how Debian could migrate to this situation.
+# Recommendations / Decisions
 
-## Describe what is desireable for buster
 
-## Mention that both setups have to be supported.
 
 === End DRAFT Resolution ===