[SVGMobile12] <handler> element is necessary?

Dear SVG WG,

15.4 The handler element

<handler> element is different from <script> element in evaluation
timing.  I think this difference is small.  Is <script> element which
is added new attribute evaluate='load'|'called', and so on sufficient?
And <handler> element has ev:event attribute.  Is <script> element and
<ev:listener> element sufficient?

example(from javahandler.svg):

<svg xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny"
     xmlns:ev="http://www.w3.org/2001/xml-events"
     xmlns:foo="http://www.example.com/foo">
     
  <desc>Example of a Java handler</desc>

  <rect id="myRect" x="10" y="20" width="200" height="300"
        fill="red"/>

  <!-- reference a jar containing an EventListenerInitializer2 object -->
  <script type="application/java-archive" id="init" xlink:href="http://example.com/myJar.jar" foo:offset="10"/>
  
  <!-- register a listener for a myRect.click event -->
  <ev:listener ev:event="click" ev:observer="myRect"
                      ev:handler="#init" />

</svg>

Best regards,

-- 
KONO Masahiko 
CANON INC.
E-mail : kono.masahiko@canon.co.jp