中文 (Chinese Simplified)
You can write MVC app yourself, but that's like development of a bicycle: it may be ok if that is your goal, but if you need to make app fast and avoid stupid bugs - it's more effective to use frameworks as they are well designed and tested. Neglecting to use frameworks is like preferring assembler.
But frameworks were never made for solving that problem. Partial content download is a nice addon, but not a goal. The goal of any framework is providing of code structure with some concepts (like MVC) to ease development. Without that it would be a library.