Not really true…I would say…you have to do the client side stuff anyway its basic UX…to have validation and so on…the thing is that the client side doesn’t really change…it is just that it automatically connects with the back-end and it gives you real time like experience…as it does all the things you would usually do with ajax…so if you have built heavy ajax apps you know how complex it can become and how hard it becomes to deal with basic things