If a recruiter were to read this article and do something like this to me, I would be totally pissed.

If I were to find out that a recruiter took the time to find extra references by rummaging around my social networks and calling people I didn't mention, I would feel some serious serious mistrust. This is the kind of thing that would actually make me reject an offer from a company.

If you have found that this technique actually works for you, then what you are actually discovering in reality is that you probably: 1) Have an inadequate technical interview process. 2) Have inadequate tech recruiters.