I'm not a huge fan of this pattern -- we might end up with every class proxying require like this, which makes it harder for static analysis tools like Browserify to infer dependencies.  Although, in this case, all the model/collection dependencies are dynamic, so Browserify already needs an [aliasMappings](https://github.com/airbnb/rendr/blob/220bfdf9c6ece4e84dd4f3d3308c5ea10baa9a7d/examples/00_simple/Gruntfile.js#L73-L79) configuration option to work properly, so it's no big loss.

I would be interested to try to use [proxyquire](https://github.com/thlorenz/proxyquire) for stubbing out `require` in tests.