How does the fact that she previously traveled that stretch at a reasonable 36mph contribute to the discussion? If the point is to determine her guilt, it misses the mark. It does, however, come off as insensitive to the deceased.
In any case, I've seen a lot of analysis on braking times/distance vs speed. To this I will just add that I have a number of friends who have been taken out by vehicles suddenly turning in front of them -- it is one of the great dangers of riding. As to why that happens, it's typically either: the driver failed to account for the cyclist's speed, or failed to notice the cyclist.
And as for Skyline, there are a number of factors that make it a dangerous road to be on. One is the large number of car and motorcycle enthusiasts who drive its length at reckless speeds (doesn't seem a factor here, but motorist deaths are extremely common on Skyline). Another is the high contrast lighting conditions the trees paint on the road -- something I always worry about when I ride that road for any sizeable stretch.
To be honest, speed is your friend up there. The closer your speed matches the passing traffic, the safer you are. At least until someone turns into you, and then the only safe speed would be no speed at all.