Exactly. And TFA jumps to conclusions about speeding and reckless driving with only some quoted speculation. FWIW, your speculations make more sense to me.

Your speculation about "fatalities [being] higher in areas where there are larger concentrations of vehicles going drastically different speeds" is consistent with what data I've seen. And it's not just about intersections. In some states, ~official policy is that drivers ought to move with traffic, even if traffic is moving faster than the speed limit.

Edit: carelessness