Development and production behavior difference

I get different behavior between the dev and prod versions of ember. I’ve changed config.ember.variant from :development to :production and back. Specifically I am creating a new record and pushing it onto a DS.HasMany array. Ember inspector shows that the record is created. Using dev the new record is displayed on the page, but with prod it is not.

Also I have confirmed that the dev and prod versions are the same:

Version: v1.0.0-175-gc374b0a
Last commit: c374b0a (2013-09-25 21:09:50 -0700)

Ember Data
Last commit: 84b3246 (2013-09-26 07:56:52 -0700)

Are there circumstances where dev and prod could behave differently, or is this a bug somewhere?

EDIT: admittedly I was doing something slightly weird. Overwriting the hasMany PromiseArray with a HasMany array so I could pushObject onto it. I changed it to simply push the new child record on in setupController (for whatever reason this didn’t work when I tried it before). This does work now, but my question still stands.

This contains a quick sample test of how this issue is affecting me.

With ember.js build, Em.keys will return the expected object keys. With ember-prod.js build, Em.keys won’t return the expected keys UNTIL you interact with the form those key/values are binded to.

Writting the issue in the repo.