Many developers try to plump for a fully-grown all-singing, all-dancing Javascript library such as mochikit, jquery, prototype or extjs, in an attempt to either augment the “View” with javascript, or to help them work-around the terrible obtuseness that is Javascript. What these libraries do for such developers, as far as the MVC model is concerned, is get them deeper into the mess, as they not only introduce a monstrous additional dependency with which they will never fully become familiar or confident with, should it go horribly wrong or not be up to the task (thus forcing the Business to adapt to the technology - the absolute Cardinal Sin of I.T. development), but also the split between the programming language used by the Web Server, and that of the Web Client deepens yet further.