A recent discussion with co-workers led me to produce this screencast [1] to try and grok the Dependency Inversion Principle and Inversion of Control (IOC) in the realm of front-end code.
I'm not familiar with Backbone.js so I think some of the "ah-ha" was lost to me. I thought it looked more like bug fixing since the first method without Dependency Injection didn't work entirely and Dependency Injection should as I understand it just make code more flexible.
The comment on zeroed setInterval's clearing the stack were appreciated though, something I'll keep in mind.
[1] - http://www.youtube.com/watch?v=mU1JcPikdMs