Re:

I believe in some other countries, the assumption is just that the largest
vehicle is to blame, unless they can attest otherwise. That methods sounds
good to me. Someone in a car can easily not pay attention for a second and
ruin a life. On a bike, it's much harder to do the same even though it lacks
powered brakes, ABS, etc since we are not in an insulated box tuned out from
the surroundings. Part of the issue is planning as well. Areas with lots of
pedestrian or cyclist traffic should never be above 20mph in my opinion, but
too often there are roads with much higher speed limits than is reasonable.
It's just too easy for an accident to happen when drivers are going faster.
Not putting the blame on them (at least to start) means that there is less
sense of responsibility.

When I drive, I generally do so around 5mph under the speed limit,
especially in dense areas. No trip is worth risking any one else's life
because I want to reach my destination a few seconds faster. It might make
impatient drivers behind me upset, but I know that when there's a line of
cars behind me, we're all driving safer and saving gas, so then I really
have no incentive to go any faster.