What test? 5th kyu? nidan?
I find it hard to wrap my mind around the idea that a 5th kyu test could not have mistakes... if there are no mistakes at 5th kyu, then that implies their technique is already perfect? They have nothing left to fix or change?
I wonder what you mean by mistakes, though... My own impression is that you just make different mistakes at different levels... And I also think you've set up a false dichotomy: you can have a test that, as you put it, 'looks like a choreographed number you might seen on the silver screen,' AND is full of flaws and mistakes... Just because you do something smoothly and 'polished' doesn't mean you're doing everything right. You may be making lots of mistakes, just making them smoothly