minor #4464 [BestPractices Removing micro-optimization note about @template (weaverryan)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #4464).

Discussion
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[BestPractices Removing micro-optimization note about @template

| Q   | A
| --- | ---
| Doc fix? | no
| New docs? | no
| Applies to | 2.3+
| Fixed tickets | -

Hi guys!

I think that a small performance gain is not a *great* reason to recommend something. And really, this was not the most important reason for recommending against `@Template`. I think it's clearer to focus on the real reason, and not get into performance (we could argue against using any feature because of performance).

Thanks!

Commits
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f439498 Removing micro-optimization note about @template

Author: weaverryan

best_practices/controllers.rst

@@ -76,20 +76,15 @@ Template Configuration
     Don't use the ``@Template()`` annotation to configure the template used by
     the controller.
 
-The ``@Template`` annotation is useful, but also involves some magic. For
-that reason, we don't recommend using it.
+The ``@Template`` annotation is useful, but also involves some magic. We
+don't think its benefit is worth the magic, and so recommend against using
+it.
 
 Most of the time, ``@Template`` is used without any parameters, which makes
 it more difficult to know which template is being rendered. It also makes
 it less obvious to beginners that a controller should always return a Response
 object (unless you're using a view layer).
 
-Lastly, the ``@Template`` annotation uses a ``TemplateListener`` class that hooks
-into the ``kernel.view`` event dispatched by the framework. This listener introduces
-a measurable performance impact. In the sample blog application, rendering the
-homepage took 5 milliseconds using the ``$this->render()`` method and 26 milliseconds
-using the ``@Template`` annotation.
-
 How the Controller Looks
 ------------------------