title: Redirect after POST doesn't change URL
body: <p>I'm using the "Redirect After Post" (http://en.wikipedia.org/wiki/Post/Redirect/Get) pattern to solve the problems with refreshing that it solves, but I'm not seeing the URL change after the POST and subsequent GET.</p>
  
  <p>Here is my setup:</p>
  
  <p>I have a form with some pretty extensive client-side validation, then submit.</p>
  
  <pre><code>@using (Html.BeginForm("AddItem", "Order", FormMethod.Post, new { Id = "addItemForm" })) 
  {
      // form stuff
  }
  </code></pre>
  
  <p>Client-side validation:</p>
  
  <pre><code>$('#addToOrder').click(function () {
      // do a bunch of validation stuff.
  }
  
  if (criteriaMet) {
      $('#addItemForm').submit();
  }
  </code></pre>
  
  <p>"AddItem" controller:</p>
  
  <pre><code>public class OrderController {
  
  [HttpPost]
  public ActionResult AddItem(long? orderId, long menuItemId) 
  {
      if (oneConditionIsTrue)
      {
          return RedirectToRoute("NamedRoute1", new { RouteValueDictionary values });
      }
      else
      { 
          return RedirectToRoute("NamedRoute2", new { RouteValueDictionary values });
      }
  }
  
  public class NamedRouteController
  {
      public ActionResult NamedRouteAction
      {
          // do some stuff
          if (mobile)
          {
              return View("MobileView", model);
          }
          else
          {
              return View("RegularView", model);
          }
  }
  </code></pre>
  
  <p>After redirecting from the POST action (AddItem), I can step things through the GET action to the return (either one).  I would expect the URL in the browser after all of this to be <a href="http://mydomain.com/NamedRoute/NamedRouteAction" rel="nofollow">http://mydomain.com/NamedRoute/NamedRouteAction</a> but it's <a href="http://mydomain.com/Order/AddItem" rel="nofollow">http://mydomain.com/Order/AddItem</a>.  Why is this?  Shouldn't the RedirectToRoute change the URL?</p>
  
  <p>What am I missing?</p>