Tweak drafting note in 4015

Author: jwakely

xml/issue4015.xml

@@ -855,7 +855,11 @@ member <tt>val</tt>
 <p>
 [<i>Drafting note</i>: Normatively, this subclause doesn't require any changes, but Daniel suggested to replace
 phrases of the form "[&hellip;]initializes the contained value with"] by "[&hellip;]initializes <tt><i>val</i></tt> with"
-as we do in <sref ref="[expected.object.cons]"/>.]
+as we do in <sref ref="[expected.object.cons]"/>.
+I think this is an improvement, since the edit to [optional.ctor] above does
+not actually say that `val` <i>is</i> the contained value, so the changes
+below make it clear that we begin/end the lifetime of `val`, not something else.
+]
 </p>
 </blockquote>