On the Thoughtworks Technology radar - they put Java Server Faces on Hold - stating:
We continue to see teams run into trouble using JSF -- JavaServer Faces -- and are recommending you avoid this technology. Teams seem to choose JSF because it is a J2EE standard without really evaluating whether the programming model suits them. We think JSF is flawed because it tries to abstract away HTML, CSS and HTTP, exactly the reverse of what modern web frameworks do. JSF, like ASP.NET webforms, attempts to create statefulness on top of the stateless protocol HTTP and ends up causing a whole host of problems involving shared server-side state. We are aware of the improvements in JSF 2.0, but think the model is fundamentally broken. We recommend teams use simple frameworks and embrace and understand web technologies including HTTP, HTML and CSS.
As I understand it, they're basically saying you can fall into a trap if you wrap a stateless protocol like http with a stateful abstraction. ie that a team can run into trouble wrapping their heads around this.
My question is: Is there evidence to suggest Thoughtworks' assertion that JSF is a broken abstraction?