title: numberOfRowsInSection called but not cellForRowAtIndexPath in MultipleDetailViews sample of apple
body: <p>If you download this sample (ipad): <a href="http://developer.apple.com/library/ios/#samplecode/MultipleDetailViews/Introduction/Intro.html" rel="nofollow">http://developer.apple.com/library/ios/#samplecode/MultipleDetailViews/Introduction/Intro.html</a>
  and you set a breakpoint at numberOfRowsInSection and also at cellForRowAtIndexPath and you start in landscape then i have the following question:</p>
  
  <p><strong>First</strong>: the app comes twice in numberOfRowsInSection -> <em>"why 2 times? Because there are 2 sections.. oké, but where did they define that there are 2 sections?"</em></p>
  
  <p><strong>Second</strong>: the app comes twice in numberOfRowsInSection and then calls cellForRowAtIndexPath -> <em>no questions here... this is normal</em></p>
  
  <p><strong>Third</strong>: when i change to portrait mode and press the popoverbutton the app calls numberOfRowsInSection 3 times and never called cellForRowAtIndexPath -> <em>"why 3 times? Why dont he call cellForRowAtIndexPath"?</em></p>
  
  <p>Thanks in advance!</p>