While I strongly agree with the spirit of this, I feel there are enough exceptions to this principle for it to be more pragmatically put.
For example:
Take a two lane road with no median barrier. Whether cycling, motorcycling or driving I have no choice but to trust that road users coming towards me stay on their opposite side of the road. I have to hope that they are not subject to a moment's distraction, or mechanical failure, or drunk. It's almost impossible to anticipate and avoid incidents like this. If I was a victim of such an incident does that automatically mean I didn't take enough responsibility for my wellbeing? Or does it mean I judged the risks of using a public road and was unlucky, whether due to someone else's dumbassery or otherwise?
My point is that there are many incidents that a diligent, innocent road user simply cannot avoid, and we shouldn't be so quick to apportion responsibility.
That's an interesting example, as if I trusted oncoming cars to stay on their side of the road I'd be dead many times over. It's very common for cars to pull a few feet over the center line to go around an obstacle (such as a bike going their direction...) without adequately checking if the space they're pulling into is unoccupied. This is one of the reasons you want to stay toward the center of your lane rather than drifting towards the middle of the road, even when a bend in the road would make that the natural thing to do.
I don't mean blind trust of course, and you state everyday occurrences of which we should all be ready for.
What I mean is a more drastic change, completely leaving their lane and entering yours with no warning. In the case of a serious and immediate mechanical fault with wheels, steering or brakes on a bend, neither party can predict or prepare for this.
For example: Take a two lane road with no median barrier. Whether cycling, motorcycling or driving I have no choice but to trust that road users coming towards me stay on their opposite side of the road. I have to hope that they are not subject to a moment's distraction, or mechanical failure, or drunk. It's almost impossible to anticipate and avoid incidents like this. If I was a victim of such an incident does that automatically mean I didn't take enough responsibility for my wellbeing? Or does it mean I judged the risks of using a public road and was unlucky, whether due to someone else's dumbassery or otherwise?
My point is that there are many incidents that a diligent, innocent road user simply cannot avoid, and we shouldn't be so quick to apportion responsibility.