[flexcoders] Basic inheritance question

[jairokan]

Hi,
I'm reading the Developer's Guide and in the section using Events, they
say on a paragraph that :
"If you try to call another method on the currentTarget (for example,
the setStyle() method), Flex returns an error. The setStyle() method is
defined on UIComponent, a subclass of DisplayObject. Therefore, you must
cast currentTarget to UIComponent before calling the setStyle() method"
for example:
<mx:Script>
<![CDATA[
      import mx.core.UIComponent;

      private function myEventHandler(e:Event):void {
         UIComponent(e.currentTarget).setStyle("color", "red");
      }
   ]]>
</mx:Script>

and e.currentTarget is of type Button. But Button extends UIComponent,
so we don't have to upcast the reference because setStyle method is
public and is available to Button object reference0. I tried the code
without upcasting and it works.
Is the writer wrong or Am I missing something on the concept.

Thanks

Jairo