From aa2f433afc9f582bfceadb3a4fb1407bc23843f8 Mon Sep 17 00:00:00 2001
From: Georg Lukas <georg@op-co.de>
Date: Wed, 22 Feb 2017 13:50:20 +0100
Subject: [PATCH] XEP-0280: stricten delivery rules from MAY to SHOULD

---
 xep-0280.xml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/xep-0280.xml b/xep-0280.xml
index fffb7d1d..1980f237 100644
--- a/xep-0280.xml
+++ b/xep-0280.xml
@@ -278,15 +278,15 @@
 <section1 topic='Messages Eligible for Carbons Delivery' anchor='which-messages'>
   <p>The focus of this specification is instant messaging applications and so those (and only those) &MESSAGE; stanzas used for instant messaging SHOULD be delivered as Carbons.</p>
 
-  <p>Defining precisely which messages are used for instant messaging and which are not is difficult, as future specifications may add additional payloads used for, or not used for, instant messaging; as such, the rules for which messages are eligible for carbons delivery is left as an implementation detail for servers.</p>
-  <p>The following is a suggested set of rules a server MAY use, or it MAY use its own; in either case it SHOULD follow the general intent of these rules. A &MESSAGE; is eligible for carbons delivery if and only if at least one the following is true:</p>
+  <p>The following is the set of rules that a server implementation SHOULD use to determine which messages should be carbon-copied. Future specifications MAY add or override rules, though they are generally advised to <link url='#avoiding'>use the &lt;private/&gt; element</link>.</p>
+  <p>A &MESSAGE; is eligible for carbons delivery if it does not contain a &lt;private/&gt; child element and if at least one the following is true:</p>
     <ul>
       <li>it is of type "chat".</li>
       <li>it is of type "normal" and contains a &lt;body&gt; element.</li>
       <li>it is of type "error" and it was sent in response to a &MESSAGE; that was eligible for carbons delivery (Note that as this would require message tracking and correlation on the server, it is unlikely to be generally appropriate for most implementations).</li>
       <li>it matches the MUC-related rules outlined below.</li>
     </ul>
-    <p>To properly handle messages exchanged with a MUC (or similar service), the server must be able to identify MUC-related messages. This can be accomplished by tracking the clients' presence in MUCs, or by checking for the <tt>&lt;x xmlns="http://jabber.org/protocol/muc#user"&gt;</tt> element in messages. The following rules are suggested for MUC-related messages:
+    <p>To properly handle messages exchanged with a MUC (or similar service), the server must be able to identify MUC-related messages. This can be accomplished by tracking the clients' presence in MUCs, or by checking for the <tt>&lt;x xmlns="http://jabber.org/protocol/muc#user"&gt;</tt> element in messages. The following rules apply to MUC-related messages:
     </p>
     <ul>
       <li>A &MESSAGE; of type "groupchat" SHOULD NOT be carbon-copied.</li>