seymores: I think you have a valid question. There is some inconsistency between when strings are passed verses a reference to a static variable. I assume passing strings around though is the more accepted behavior because it is less cumbersome than Ext.Layout.NORTH for example. If one ever needed to find all instances of using the north layout region, they could be confident doing a search for Ext.Layout.NORTH but not as confident searching for 'north'.