@ericf, you mentioned:

> Why do we need these defaults? How do you imagine they'll be used at this level?

This makes it possible for a user to go to `/start/` and have the client-side model populated with sane defaults. 

> This value of '5,24' seems un-helpful. Why would this be parsed into an array (and are you sure Express doesn't already do this?)

Express didn't do any sort of string => array manipulation. This value gets parsed into an array in the model's setter on the client-side.