I have a visual force page that basically lists a bunch of elements, allows you to select an element, and then shows you certain details of the element you selected below the list.  The page has the structure (summarizing) :

<apex:page>
  <apex:form>
    <apex:pageblock>
       <apex:pageBlockSection>
           <apex:pageBlockTable> <!-- this is my list -->
           </apex:pageBlockTable>    
      </apex:pageBlockSection>
      <apex:pageBlockSection >  <!-- this is my details, rendered only if something selected -->
      </apex:pageBlockSection>
    </apex:pageBlock>
  <apex:form>
</apex:page>

The rendering/visibility aspects all work fine (ie when I click an item in my list, it calls an apex function that ensures the details section is visible, etc).   But I always return to the top of the page when I'd like to return to the bottom or details section of the page. 

One way I can get around this is to reconstruct a URL/PageReference and load it up with the parameters required to get me back to this state, ie something like: 

PageReference pr = ApexPage.currentPage();
pr.setAnchor('mainPage:mainForm:mainBlock:detailsSection');
pr.setRedirect(false);
pr.getParameters().put('detail', detailId);
pr.getParameters().put('id',mainId);
return pr; 

That works, but it basically reloads the entire page in the browser (ie the browser sees the new URL).   I thought that if I could just return an anchor marker from the function that it might jump to that page section without reloading the page, ie without adding the parameters:

PageReference pr = new PageReference('');
pr.setAnchor('mainPage:mainForm:mainBlock:detailsSection');
pr.setRedirect(false);
return pr; 

It says its returning '#mainPage:mainForm:mainBlock:detailsSection' as the return value (from a system debug command just before the return), but it also ends up either hanging the browser or reloading the entire page (which doesn't work unless I add more parameters to get me back to the correct state).  

I was wondering if there's an easier way to move around in the page (so I can go to a specific anchor/section of the page after performing a specific apex function to pull the details of the record from the database) that doesn't require the browser reloading the entire page.  Any suggestions?