Oh, you mean clear, dry, wide open road right? 70 or 80 mph, no problem.
What happens when the average guy blows a front tire at 80? Or when the guy in the number 4 decides he wants to be in the number one where the average guy is doing 78 mph?
Drive to conditions means nothing, as those conditions can change in a split second.
I have those situations happen and people spin out and avoid all those cars while driving at interstate speeds on interstate roads. I have had bikes and people pull out in front and people make left turns from right lanes. I do try to read the behavior cues and react according. Remarkably I have avoided hitting people in those situations. However accidents is usually being in the wrong place at wrong time. All drivers do something stupid once in a while. Generally it is when no one else is around to have an accident. I am trying to say I do not consider myself stunt drive expert. However competent aware drivers usually don't have accidents whether they speed or not.