Why does Apple's doc say that you don't call the superclass's event handling methods in subclass of UIView?
<p>In Apple's document, Event Handling Guide for iOS, the section "<a href="http://developer.apple.com/iphone/library/documentation/EventHandling/Conceptual/EventHandlingiPhoneOS/MultitouchEvents/MultitouchEvents.html#//apple_ref/doc/uid/TP40009541-CH3-SW18" rel="nofollow">Best Practices for Handling Multitouch Events</a>":</p>

<pre><code>If you handle events in a subclass of UIView, UIViewController, or (in rare cases) UIResponder, 
  You should implement all of the event-handling methods (even if it is a null implementation).
  Do not call the superclass implementation of the methods.
</code></pre>

<p>and</p>

<pre><code>If you handle events in a subclass of any other UIKit responder class,
  You do not have to implement all of the event-handling methods.
  But in the methods you do implement, be sure to call the superclass implementation. 
</code></pre>

<p>Why? I don't understand the rationale behind point 2 of both cases. Doesn't it depend on the different situations?</p>
