I think this is a gray area. You cant reasonably expect to stop a car from driving the speed limit if you come across an obstacle that is not visible due to terrain. The blanket it is always your fault I think would fail that litmus test.
Yes, but if you looked at google maps on the roads, it is pretty long and straight-ish around that area. It isn't like he just rounded up over a hill which is blind and they were just at the downhill side of it. And it is your guidance. hence the defensive driver. Use caution.
If your coming to an obsticle that hinders your vision, it is your job to do what it takes to ensure safety for everyone. Even blind spots. (slow down, honk horn loudly, etc.)
This is also why the driving test is a joke. They should really force people through a blind spot or 2 and see if they do what it takes to prevent issues.
Now, if the driver (sober) was to leave a blind spot, and all the sudden see people/stopped car on the side of the road unexpectadly and he was to dodge them and hit some other property/thing, you could question that the people in the road were causing a hazard.