Sure, in the short term. I generally find that understanding the system (or building abstractions that cover the complex system in sensible ways), you find ways

Sure, in the short term. I generally find that understanding the system (or building abstractions that cover the complex system in sensible ways), you find ways to solve problems more elegantly. Put another way, in building an app, I always learn something about my original vision of the app that was wrong, and needs correcting. ExtJS doesn't help with that iteration loop: I just create hard-to-debug things that do exactly what I want when I finally get them working. The rubber of your ideas meeting the road of the complex system is an important step in creating a better app, and papering over the system ignores that step.