Argh, forget I said any of this, "Here's how I think the pattern would look like if we were to use nested routes. The notable changes are in routes.rb and users#show in."

This is really interesting, so we're forced to use a hidden field no matter what? I was wondering if you would be able to explain me what this guy was saying in regards to the hidden field: http://stackoverflow.com/questions/3339735/any-way-around-putting-hidden-field-in-forms-for-resources-with-belongs-to-assoc