Re: Overriding/Redefining a Non-Virtual Function in Derived Classes

In Scott Meyers' "Effective C++", item 36 states "Never redefine an
inherited non-virtual function". This admonition is repeated at item 23.8
of C++ FAQ Lite ("[23.8] Should a derived class redefine ("override") a
member function that is non-virtual in a base class?" at
http://www.parashift.com/c++-faq-lite/strange-inheritance.html#faq-23.8 ).

I only just now recognized that in the MFC framework, this is done all the
time. Particularly with respect to message handlers for CWnd-derived
classes, it's common to see code like:

BOOL CDerivedWnd::OnEraseBkgnd(CDC* pDC)
{
  // call base class function, which is not a virtual function
  CWnd::OnEraseBkgnd(pDC);
  // ... code specific to derived class
  return TRUE;
}

I recognize that MFC is not a paragon of C++ good-programming
practices. It is also my understanding that the programming
of message handlers for CWnd-derived classes was an attempt to
*avoid* virtual functions.

But given the fact that it is used so extensively by the MFC
framework, is it truly such a bad idea to override/redefine
non-virtual functions in derived classes? Is it truly
something that should be left to "experienced C++
programmers", as mentioned in the C++ FAQ Lite?