"Personally I don't find it useful because it tries to separate knowing from doing." What do you mean? Learning and doing are quite different. From a professi

"Personally I don't find it useful because it tries to separate knowing from doing." What do you mean? Learning and doing are quite different. From a professional programmer point of view: If it takes me 6 months to learn a tool, and then the tool allows me to complete future work twice as fast (or with half as many defects etc) that is a great trade off.