It also depends on how the picture is inserted. If you're working in
compatibility mode and insert the picture as a link, Ctrl+Shift+F9 will work
as advertised since it creates an IncludePicture field.. If you're working
in a Word 2007 document, however, the method has changed, and you do not get
a field code when you choose link if you're going through the Insert -
Picture command. You get something else for which Ctrl+Shift+F9 does not
work (when you press the combo, you'll get a Ding, instead). It's possible
that the OP's friend was using .docx format.
You can still use the IncludePicture field in .docx formatted documents, but
you either need to do it manually or use the Insert...Field method.