title: When can't you use SafeHandle over Finalizer/IDisposable?
body: <p>When seeing about the whole finalizer/IDisposable issue, it is usual to see that, at the end, after all the long description, there will be something to the meaning of "LOL what I said was actually useless, you should use SafeHandle instead bye!"
  So I am wondering in what case does SafeHandle not fit, such that you have to resort to the finalizer/IDisposable old way?</p>