Anyone who has read my various posts on this subject over the years knows this already.
Speed isn't a factor in most accidents because roads are "over-designed" to accommodate vehicles traveling much faster than the posted speed limit -- which is why reducing speed limits to improve safety is ridiculous.
A posted speed limit is simply a statutory limit that has nothing to do with the safe operating speed of the roadway in question -- especially for newer roads. If you're on a highway with a posted speed limit of 65 miles per hour, you can probably drive 80+ miles per hour without exceeding the "design speed" of the road. And keep in mind that the design speed under AASHTO design standards is based on stopping sight distance on wet pavement.