To answer my own question. The following worked.
What I found was that when creating the accordion object, you define no animation first.
Then, select what section you want displayed at load time. In my case my Kohana controller
retrieves this from a session variable set by the previous form submission. It then gets passed into the template containing this code.
After thats done, set the animated setting to slide and it's all go from there.
$(function(){
/* Create the accordion object first */
$("#accordion").accordion({ animated: false, header: "h3", autoHeight: false, clearstyle: true, collapsible: true })
/* get the section to load. This is set by the previous form submission and saved to a session variable. */
var id = <?php echo $sectionId; ?>;
/* activate on sectionId=0 causes it to close (which is by design) this gets around it */
if (id != 0) {
$("#accordion").accordion("activate", id);
}
$("#accordion").accordion("option", {animated: "slide" });
});