Interesting article. I didn't know about JSP Model 2. Another detail that's not mentioned, but very useful for understanding the original pattern, which is des

Interesting article. I didn't know about JSP Model 2. Another detail that's not mentioned, but very useful for understanding the original pattern, which is described in [1], is that controllers had a specific and unique responsibility in the original system where the MVC pattern was defined: The system gives the input focus to a controller, not to a view, so you can't accept keyboard input without a controller. So, unlike pretty much every other GUI toolkit, it's not a matter of having the view delegating input to a controller as a matter of good design, but rather that the controller is simply the way that the system provides the input to the application – you have no choice in the matter. This also meant that there was one controller per widget that could receive focus (corresponding to each HWND in win32), not just one controller per screen. The same document also contains answers to some frequently debated questions about the true, proper and orthodox way to do MVC: Should the view subscribe to model or should the view updates be mediated by the controller? Should the model represent the pure domain logic or also contain view-level state? Should the model be a simple value object or also contain domain logic? It turns out the answer is: All of the above! The original MVC in Smalltalk apparently used all of these options in different applications depending on the circumstances. [1] https://web.archive.org/web/20100921030808/http://www.itu.dk/courses/VOP/E2005/VOP2005E/8_mvc_krasner_and_pope.pdf https://web.archive.org/web/20100921030808/http://www.itu.dk...