Uncommented diff: define expected <path-identity>

I proposed the following diff in response to one of the previous
discussions, but I don't think I ever got any feedback and hence never
applied it.  Could people look this over and tell me if it should be
included?

This change goes into the section defining the Path header field.

Index: usepro.xml
===================================================================
--- usepro.xml	(revision 5041)
+++ usepro.xml	(working copy)
@@ -405,7 +405,13 @@
                   followed by the FQDN, IP address, or expected
                   &lt;path-identity> of the source.</t>
                 </list>
-              Be aware that <xref target="RFC1036" /> did not include
+              The "expected &lt;path-identity> of the source of the
+              article" is a &lt;path-identity> for the injecting or
+              relaying agent that passed the article to this relaying or
+              serving agent, determined by properties of connection via
+              which the article was received (for example, an
+              authentication identity or a peer IP address).  Be aware
+              that <xref target="RFC1036" /> did not include
               &lt;path-diagnostic>.  Implementations which predate this
               specification will add only single "!" characters between
               &lt;path-identity> strings.</t>

-- 
Russ Allbery ([email protected])             <http://www.eyrie.org/~eagle/>