This has been studied to death. The danger increases with the deviation from the mean travel speed. What this means is that people who drive significantly lower than the mean speed cause just as many accidents as those going significantly above it. However, because people traveling too slow annoy other drivers, slow…

As a Michigander I can confirm that the speed of traffic was 80-85 before the speed limit raise and it remains 80-85 after the speed limit raise. No one does 70-75 any ways.

Counting crashes and fatalities is meaningless. You need to count crashes per car-mile traveled. Higher speed limit highways always attract more traffic. If there was a 20% increase in traffic and a 20% increase in fatalities, that’s not exactly terrible news.