Working with :before / :loading

Simple question…

Within my view I have the following:
<%= observe_form ‘interest’, :frequency => 0.25,
:update => ‘search_target’,
:url => { :controller => ‘desk’, :action => ‘results’ },
:before => “Effect.Fade(‘animation’);”%>

I’m using :before to try to apply a fade to the layer before the results
come up. Unfortunately, before the fade can even come close to
finishing, the new page is displayed. Is there any way to slow down the
loading or rather to specify how much time before the results action can
be queried?