It's interesting that you can replace "documentation" with "tests" in your argument and it's still an argument people make. It's double work you have to write t

It's interesting that you can replace "documentation" with "tests" in your argument and it's still an argument people make. It's double work you have to write tests and code! Yup, it is, kind of. I'm not necessarily assuming which side of the argument is right -- for docs or tests. Certainly "starting something new spontaneously just by starting to hack" can be useful and fun. And may not involve tests or docs. That's sometimes called a "spike" (although that's not exactly what the term "spike" was meant for, I think). I find that generally after an initial period of spontaneous experimentation, getting a sense of what might work or not and what direction I might want to go--it's generally best to move to a less spontaneous development process. That will likely involve test coverage (whether strictly TDD or not). I think thats probably also the point to consider "test-first development" too.