I was thinking... I am used to doing the classic MVC style of using Url.Actions to call methods and then return a view (even the same view) with a view model.
But then as I thought about jquery and AJAX I thought.. .if the page (view)does not change shouldn't I always use jquery ajax for my commands???
For examples I have a MVC application that you click a button and calls a Url.Action method which performs a long running method.. so from the user point of view the browser hangs for about a minute... But if I used jquery ajax I could call that method... have it return immediately and then I could perhaps set up a timer that calls another method to show progress of this long running process...
So is my theory correct? ALWAYS use jquery ajax for methods that return the same page. ALWAYS use Url.Action for methods that return a new page.