I'm attempting to replace the contents of a div, "stupidtest", using
ajax->observeField.  The event is observed, the post occurs, but the
contents of the div are simply destroyed.  The same arguments sent to
ajax->link work correctly.

In other words, the second line clears the div contents, and the third
one sets them appropriately:

$options = array('update'=>'stupidtest','url'=>'/decks/
stupid_test','frequency'=>1);
echo $ajax->observeField('DeckName', $options);
echo $ajax->link('Manual Ajax', '/decks/stupid_test', array
('update'=>'stupidtest'));

This occurs on both my local xampp setup as well as a remote LAMP
environment, on CakePHP 1.2.5.  Perhaps I'm missing the basic concept
of how observeField functions?

In case it's not something simple, I've pasted in my stripped-down
test case.  I created it in the hopes it'd help me figure out what's
going wrong, but no luck so far!

Full controller source: http://bin.cakephp.org/view/2126548994
Full view (ajax_test.ctp) source: http://bin.cakephp.org/view/1853385069
Full view (stupid_test.ctp) source: http://bin.cakephp.org/view/404720761

Much obliged to anyone who helps me figure out my error with
observeField.  I read a number of examples, but was unable to see
where mine differs.