docs/AntiAbuse: clarify that `#stop-join-flood` may be shared

doc/AntiAbuse.md

@@ -59,8 +59,8 @@ PBot performs its join-flood enforcement in a separate channel to reduce noise i
 
 Let's say you want to set up join-flood enforcement for channel `#bash`. Here are all of the steps required to do that.
 
-* Create and register the `#stop-join-flood` channel. This is where PBot will forward join-flooders. Give it a sensible `/topic` like "You have been forwarded here due to join-flooding. If your IRC client or network issues have been resolved, you may `/msg PBot unbanme` to remove the ban-forward."
-* Create and register the `#bash-floodbans` channel. This is where PBot do the banning/unbanning. Give PBot channel OPs here.
+* Create and register the `#stop-join-flood` channel. This is where PBot will forward join-flooders. Give it a sensible `/topic` like "You have been forwarded here due to join-flooding. If your IRC client or network issues have been resolved, you may `/msg PBot unbanme` to remove the ban-forward." If the channel already exists and has this `/topic`, great! It doesn't matter which PBot instance originally sets `#stop-join-flood` up, everyone can share it! See the next bullet-point for where your instance of PBot will perform its duties.
+* Create and register the `#bash-floodbans` channel. This is where PBot do the banning/unbanning. Give your instance of PBot channel OPs here.
 * Set an extended-ban in `#bash`: `/mode #bash +b $j:#bash-floodbans$#stop-join-flood`. This will retrieve the bans from `#bash-floodbans` for use in `#bash`.
 * Join PBot to both `#bash` and `#bash-floodbans` so it can monitor `#bash` and set/remove the bans in `#bash-floodbans`.
 * Optionally, configure the `#bash.join_flood_threshold` and `#bash.join_flood_time_threshold` registry entries if the defaults are not desirable.