title: Why is ReadOnlyObservableCollection.CollectionChanged not public?
body: <p>Why is <a href="http://msdn.microsoft.com/en-us/library/ms653378.aspx" rel="noreferrer"><code>ReadOnlyObservableCollection.CollectionChanged</code></a> protected and not public (as the corresponding <a href="http://msdn.microsoft.com/en-us/library/ms653375.aspx" rel="noreferrer"><code>ObservableCollection.CollectionChanged</code></a> is)?</p>
  
  <p>What is the use of a collection implementing <code>INotifyCollectionChanged</code> if I can't access the <code>CollectionChanged</code> event?</p>