It seems from your original comment and your reply that you're arguing that liability can be discharged if the AP system has fewer crashes per capital than humans do. You can't argue relative liability based on statistics. That's like me murdering someone and then arguing that I'm not liable because it just so happens that I didn't increase the per capita murder rate over last year. Now, whether Tesla has any claim that their liability can be discharged because the operator wasn't following legally binding instructions not to operate in that way is a different issue, and one I'm not privy to.