title: Why isn’t ReadOnlyDictionary thread-safe?
body: <p>I’m looking for a readonly-dictionary to be accessed from multiple threads.  While ConcurrentDictionary exposes such capabilities, I don’t want to have the overhead and the strange API.</p>
  
  <p>.Net 4.5 while providing such a class, the documentation states that only static calls are safe. </p>
  
  <p>I wonder why? </p>