We know driving is possible. So, check. Cost effective, I don't know what this means in this context. Development costs, rider costs? I don't see why this matt

We know driving is possible. So, check. Cost effective, I don't know what this means in this context. Development costs, rider costs? I don't see why this matters. Safety is easy to measure. Just measure crash rates. If your concern is can we engineer a self-driving car with acceptable safety performance, there is only one way to figure that out and it's to try to build one. You're not going to somehow prove it out on paper before trying it.