Joshua Schachter might be a useful example. He built Delicious while working on Wall Street. One of his most useful tricks was to build something every day, however small. I suspect that keeps your brain working in much the same way that running every day keeps your metabolism high.
That is good to hear. It seems that quality (perfection?) is secondary to actually building stuff, making mistakes, improving it, learning. As said in your essay, determination is more important than intelligence. Though "an incurable tendency to build stuff" sounds less depressing.
