A shorter audition: ask people to write code on a whiteboard or a laptop during a day long interview.
Why not at least give the appearance of trusting while still making internal judgements and while holding some sort of casual conversation about technical topics with the candidate?
OTOH, I hate having interview "homework" because they take a lot of my time but cost the company almost nothing - they can easily have a hundred people doing the homework, get one engineer to spend a day evaluating them, and then only hire one person.
A lot of people under-perform in a whiteboard/monitored situation, and for most it does not represent a real-life work environment at all.