This was one of the reasons why Backbone was my first choice compared to the other "MVC" frameworks. The documentation was simple and I think some the handling of Views helped you mentally organize your DOM manipulation code versus having a file riddled with various event bindings with possible selector conflicts hidden. Right now I am working with AngularJS but the documentation can be cryptic at times. I didn't have resources like John Lindquist's site (http://egghead.io), I may have suck with BackboneJS. It is still a great framework but AngularJS, after gaining experience, has some amazing features.
So true, that was one of my favorite things about Backbone. I don't even really look through the docs anymore, just jump straight to the source. It's incredibly well done.
Angular has _huge_ obstacles for dev usability when Backbone's source is so accessible you can use it to help learn js.