Q:

When would you us Ext.application() vs. Ext.Loader.setConfig, .require, and .onReady?

I see that some of the examples included with ExtJS 4 start up via a single call to Ext.application(). Other examples, however, manually call Ext.Loader.setConfig(), Ext.require(), and Ext.onReady() instead. I want to make sure I understand the difference.
Am I correct in assuming that:

you'd normally use the convenient Ext.application() call for a full-screen (e.g., Viewport-based) app?
if you just want to use a few ExtJS components on a pre-existing "non-Ext" page you'd opt for the manual calls to Ext.Loader, require, and onReady()?

Thanks for the clarification! 

A:

The full application call is used for the Ext MVC approach, and comes with a set of conventions to pre-load additional components, for example the stores and views options in the controller classes. For a better explanation see the Ext documentation on MVC.
If you just need to throw a few components on the page, as you state, you will get better performance just using the loader, or better, avoiding dynamic loading (at least in production).

