If WordPress would do the same, would it lose much in performance?
closed as not constructive by Chip Bennett, scribu, Rarst♦ Oct 30 '11 at 18:04
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Before trying to figure out if it would hurt performance (yes, it probably would), one should ask what the benefit of switching to Symfony would be. I have no idea, since I haven't worked with Symfony.
In general, less code and fewer levels of abstraction are better. For example, WordPress uses a very thin DB layer, instead of an ORM.
IMO, all these frameworks do one thing:
Turn Developers into users.
And I think that's bad.