It's less wasteful than central planning in most cases, but it's still wasteful.
Indeed. Urbanist thinker Jane Jacobs argued that duplication and waste is a highly important part of development work. She argued that small firms breaking off of old firms to pursue new ideas are how we get new, innovative ideas, goods and services. This process only works if there is a lot of "wasted" work being done in small, inefficient workshops, labs, etc. that fail more often than they succeed. She argues that this is one of the defining features and advantages of urban life. Cities provide an intense concentration of small businesses to support development work, and intense concentrations of people bumping into one another, creating networks, and constantly searching for new ways to build, assemble, conserve, deliver, etc, to meet one another's needs.
I'd argue that this exact process is going on with the development work springing up around Bitcoin. There's a lot of "wasteful" duplication going on in the bitcoin economy. It's being developed by small groups of highly competent, enthusiastic individuals. Much of this work will fail, but its this exact process of creation and discovery that expands an economy.
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