As a hiring manager, I look for someone who "gets things done". No surprise that this takes many things: knowledge, skill, smarts, creativity, experience, team work, and maybe most important: attitude. You have just self-identified your bad attitude. If you think this is "draconian and insulting", just wait until your knee deep in digital crap with customers barking at you all day long.
"I cannot vouch for its efficacy as I've never used it when hiring people."
I can. Nothing works better. Period. If I have 30 to 60 minutes to find out how well you'll perform, I'll have you code and teach me what you've done. I don't care what you've done before, your state of mind, or even if your code ever runs or compiles. If you're any good at all, I'll find out. If you're a poser, I'll find that out, too. And if you don't want to play along, then either you're a poser avoiding exposure or a prima donna who is saving me a lot of suffering down the road.
I'm not trying to insult you, just give an honest answer to your (very good) question.