Coming back, then, to our example of strategy instruction, the theory supporting spending a lot of time in teaching reading compre¬hension strategies is a good example of nonconvergence. It is in con¬flict with much that has been learned about the gaining of expertise and the workings of the mind. The reading strategy theory initially took note of a narrow range of data: expert readers tend to monitor their own performances. Then the theory took an unwarranted leap: if that is what expert readers do, we will take a big shortcut by teach¬ing novices how to monitor their performances. While some of the subsequent data did appear to support this approach, other data sug-gested that conscious self-monitoring is not the path that experts ac¬tually take to become experts. Studies of expertise have consistently shown a very slow development of high skill (ten years is close to the minimum time). Still other data indicate that active self-monitoring can be done effectively only after the person has become an expert –for reasons having to do with the limitations of channel capacity in the human mind. This evidence argues against burdening the nov¬ice’s mind with self-conscious strategizing. Still another theoretical shortcoming of the strategy idea was its unspoken but incorrect as¬sumption that these "metacognitive" comprehension strategies are formal, transferable activities that can be deployed independently of content knowledge. A better theory that accounted for a larger range of evidence would have avoided these scientific shortcomings and a tragic waste of classroom time.