But there's already telltales for that: if a driver consistently drives more than 10 mph over the speed limit, they'll eventually get caught and ticketed.
That's where age & experience come into play. If a driver has 20 years of experience with no tickets nor accidents, does any of the other stuff really matter? It's not just observable, it's proof - instead of assumption.
Knowing people engage in behavior objectively quantifiable as more risky is also strong evidence of increased level of risk for that driver, not an assumption that the given individual will have a given outcome.
There is a subtlety here in correlation and causation.
>I'm sure there's people out there that drive like maniacs 90%+ of the time and haven't had an accident, but that doesn't mean they aren't significantly more likely to do so in the future.
It's not 'they', it's 'their cohort', and the apparent risk can be very sensitive to the level of detail and factors accounted for - such as nut allergies.
As long as we know the ruler IS bent - because we need some way to charge people appropriately for insurance.
I would argue it is both: the "drive like a maniac" cohort is likely to see a higher incident rate across the population, and that a given individual exhibiting "drive like a maniac" behavior is more likely to have an incident themselves vs. a given individual that does not "drive like a maniac."
This is driving in the open world, not art you create in your basement. Drivers are not fully in control of their environment, and riskier driving behaviors are risky even for fantastic drivers because they cannot account for how others will react to their "mania", to keep the vocabulary consistent.
You could chart the relationship between levels of mania and some of the unaccounted factors, like driving skill or restraint. Slippery slope ends up in a trap of having to account for everything for the sake of fairness.