Yes, you can use attr to read nested objects. Not only that, but you can read nested attributes, completely ignoring if something exists currently, and if any of the attributes are computes.
For example:
Suppose states has a current state and each state has a list of cities and a current city. Now suppose that cities are lazy loaded, and so when a state becomes the current state, it'll load it's cities, and when those load, it'll automatically set the current city.
You could do something like this: States.attr('current.cities.current.geolocation');
Eventually, geolocation will be available, and so you can use this accessor to hook up to a very complex future, completely ignoring the fact that both currents are computes, and that cities is populated by a deferred object.