[Produce]

>Have you tried automated testing on a large complex web application? It's an insanely monumental task.

What's so insanely monumental about writing unit, functional (i.e. like these http://symfony.com/doc/current/book/testing.html#functional-...) and Selenium tests to cover everything before committing new changes? It's just like any other code - test the main condition and edge cases and everything will be running smoothly next time you come back to that feature.