The reason I don't like adding extra methods to classes is because by doing so you often end up adding an extra layer of dynamic dispatching. If I have that fun

The reason I don't like adding extra methods to classes is because by doing so you often end up adding an extra layer of dynamic dispatching. If I have that functionality in a static function when I read it I know that it can only do one thing but if I see a method call I have to always wonder if its going to be polymorphic.