An interview with Ryan: Ryan Singer on UI design, Frontend Development, Project Management and Inspiration (ThinkVitamin.com).
As a designer, do you need to understand frontend development?
The more you understand about frontend development, the better designer you’ll be. If you are really familiar with handcoding and you understand basic HTML markup and you know how CSS selectors work then you’re really well prepared, for example, to use the fact that jQuery and Prototype both have a way to refer to pieces of your mark-up using CSS selectors even though your not using CSS.
If you’re designing web app user interfaces, then I think it’s important to get into understanding how an MVC framework works like Rails or Django. If you can understand how your templates fit in to the view, as the “V” in MVC then that’s a huge leap. You can really start doing work with programmers and you can have ideas and you can make them into reality instead of just making designs and handing them off to somebody and hoping that someone else can plug them in.