And sadly I haven't once seen it in action. I really wish I could go through such process, or implementing it in whatever company I work at (or create).
I've set tests more or less like this in the past and I took one just the other day.
It's actually kind of interesting doing this from the hiring side because it became evident that there are a lot of relative "bargains" out there - excellent developers who do poorly in whiteboarding and chatty interviews so have lowered salary expectations but who are nonetheless very good at their actual job.
And sadly I haven't once seen it in action. I really wish I could go through such process, or implementing it in whatever company I work at (or create).