I've been asking for feedback on the Action-Domain-Responder pattern, a refinement of MVC, to discover how it's being used in the wild already, and to solicit criticism of the pattern to find weak points.

The key points of Action-Domain-Responder:

Instead of a controller class with many action methods, each Action is its own class (or closure, like with Slim).

The Action interacts with the Domain (model), and feeds data to a Responder (view).

The Responder is entirely responsible for building the response, including all headers as well as the body of the response. This means that in ADR, the template is not the view; the response is the view.

Stephan Höchdorfer has been using single-Action classes for a while now. Here is my summary of his article:

"we are using action classes in our application framework for almost the last decade"

"action classes tend to be rather small, typically less than 100 loc for us"

"another bonus point for action classes: It is easier to search for a class name than a method name"

"Controllers tend to have a lot of dependencies. ... people came up with a few "creative" solutions for this problem, mainly the creation of lazly loaded dependencies"

"action classes depend on what they really needed. Typically that's just a few services for a single action. Again that makes the code way easier to understand and easier to test."

"Action classes in contrast to controller classes can be reusable."

Those were the highlights for me; you should read the whole essay to find your own: http://blog.bitexpert.de/blog/controller-classes-vs.-action-classes

In addition, please write up your own commands and criticism regarding Action-Domain-Responder, so that I can improve the offering as much as possible.