In MVC the Controller is the go-between for the View and the Model. So the Controller should be the one that observes or receives changes from the Model and View and updates the other accordingly. I know for sure that doesn't break MVC.
But what if the Controller registers and unregisters the View as observer to the Model? What the view would know is the key path, what kind of change, and what the value is without having a reference to the model object. So if you assign
model.title = @"new title" the View can map that property change to an action, like a
UILabel subclass assigning
self.text = @"new title". Does this break MVC?