I'm not objecting to UITableViewCell subclasses to manage each type of view -- thats a nice, reusable design. getCellForTableView:controller: to return an instance of a given cell is essentially what I do (although I keep it as a class method on UITableViewCell instead).

My objection is to RootElement and QuickDialogController. What happens if you have to present a screen from multiple places? Or if you need to modify it at a later date, to, say, add another field?

For example: Say you have a login screen. And now you want to add a field to ask the user for another bit of information. With your design, you have to know everywhere that you can possibly log in from. Or, you have to add a method somewhere to set up the login view and then push it. And at that point, you might as well just make a separate controller to control everything. Which brings us back to tableView:cellForRowAtIndexPath:.