One of the best things about Castle Monorail MVC engine is that it allows us to test controllers from the IDE, without actually deploying anything to the web server. A major problem with most web development environments, including classic ASP.NET, is that the workflow and session logic can only be tested through the UI. User interface testing is slow, pain to maintain and generally does not pay off as much as code unit tests do. Monorail’s programming model allows us to test workflow and session logic from the code, leaving only the actual rendering outside the reach of unit tests. That is how Monorail empowers us to really apply agile principles to web development, and saves us even more time and effort.