In a previous post of his Dave Marshall talked about using controllers as "services" in a Silex-based application. In this new post he takes it a step further and shows you how to use route helpers to make working with those controllers even simpler.
Supposing we want to render some HTML, do we want to inject the template engine in to the controller? Should the controller be responsible for knowing how to render the template? I'm not sure, but if I can have it not do it with minimal fuss, I think I'd rather it not. The full stack framework has the @Template annotation, which allows developers to assign a template to a controller and then simply return an array. If they can do it in the full stack framework, we can do it in Silex.
He includes the code for an example of a 404 handling page that uses the "convert" method to configure a route (path to a controller) for the currently matched route. He also shows the creation of a simple "CustomRoute" class and a "TemplateRenderingListener" to make it simpler to customize the handling and output of the request, all injected into the application's DI for later use.