I have to ride across an expressway, and about two miles of busy 35 mph (50+ mph actual) road. Honestly, I ride straight and predictably, slightly out from the right shoulder and no one usually bothers me. I guess to alleviate fear when I hear a truck racing up behind me, I always think that motorists may be annoyed and want to intimidate me, but 99.9% will stop short of physically harming me. Not a lot of people are looking to have assault, manslaughter or murder charges on their hands.