[#2926] Minor tweaks

Author: weaverryan

book/templating.rst

@@ -670,9 +670,8 @@ string syntax for controllers (i.e. **bundle**:**controller**:**action**):
 Whenever you find that you need a variable or a piece of information that
 you don't have access to in a template, consider rendering a controller.
 Controllers are fast to execute and promote good code organization and reuse.
-This however should not encourage many fat controllers but rather
-to create services used within few view-oriented thin controllers that 
-just render those pieces needed.
+Of course, like all controllers, they should ideally be "skinny", meaning
+that as much code as possible lives in reusable :doc:`services</book/service_container>`.
 
 Asynchronous Content with hinclude.js
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