[mattkrause]

I would happily sign a waiver for some feedback.

That said, I would bet that a lot of decisions, especially among "finalists" are essentially random (who seems smarter/better put together/whatever).

You're not going to get someone saying "well, you took 10.3 minutes to sketch out a solution to our first problem, which was too long. We would have hired you if you finished in under 9 and half minutes though."