I love this. Software developers too often focus on the final end state and this distracts from the state changes in the middle of any process. By focusing on

I love this. Software developers too often focus on the final end state and this distracts from the state changes in the middle of any process. By focusing on UI responsiveness you vastly improve discoverability and interoperability because it naturally decouples the problem into a model/view/controller design. Best of all you can't mis-design: the responsiveness is your constraint, and if the design doesn't give you responsiveness you KNOW it is a poor design. This is the ultimate quality litmus test.