What is the most stressful part of driving your coach?

idiot drivers who do not know how to merge into traffic from an interstate entrance ramp. I usually travel in the right hand lane and can see them coming dowm the ramp. if I can I will move over. I frequently see these nervous nellies slow down while coming down the ramp rather than accelerate. we've even seen several simply stop at the bottom of the ramp. if they're that afraid of the interstate then they should find an alternate route.