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What I saw around me was a community that had evolved the most effective software-development method ever and didn't know it!. That is, an effective practice had evolved as a set of customs, transmitted by imitation and example, without the theory or language to explain why the practice worked.
In retrospect, lacking that theory and that language hampered us in two ways. First: we couldn't think systematically about how to improve our own methods. Second: we couldn't explain or sell the method to anyone else.