Teaching and Learning

Just saw this in the Psychologist (thanks SF):

The sad truth is that lecturing is easier than the alternatives, and lecturers can always kid themselves that teaching equals learning. It reminds me of a cartoon I once saw where a dog owner tells his friend that he has taught his dog to whistle. The friend says, "I can't hear him whistling", to which the dog owner replies, "I said I'd taught him to whistle, I didn't say he could whistle!"