Reading your post made me realize that I've unwittingly used your technique, without clearly understanding why it works.

When hiring for an intern/junior position, I will often ask for a sample of a candidate's school projects. My rationale for this request is to see an example of their code. In practice, some candidates never follow up on my request; some send me a big hairy zip file with no context; and some obviously take the time to clean up their code and add comments before sending it to me. I've even had one or two create a GitHub account and push their code to a public repo to share with me, after we've gotten to talk about their knowledge of git.

Thank you for the insight that while trying to gauge technical skill I ended up evaluating thoroughness and care ;)