http://blog.danielribeiro.org/yes-you-can-have-low-coupling-in-a-symfony-standard-edition-application/

这是作者一年使用后分享的经验

http://stackoverflow.com/questions/9999433/should-everything-really-be-a-bundle-in-symfony-2-x

关于解耦合讨论，比如不用symfony了，怎么让核心程序还能用