Don't think this is the right way since ```ActionController::Renderers.add``` defines a method as shown:
```ruby
    # renderers.rb
    def self.add(key, &block)
      define_method("_render_option_#{key}", &block)
      RENDERERS << key.to_sym
    end
```

I was considering adding a remove method but I don't think there will be an actual use case for it in an app.