We have quite a few out of state drivers in So Cal highways. Most out of state license plates from NY, MN, MA ... on infamous I-405, I-5 are so slow on middle lanes cars had to brake hard to avoid accident and quick lane change to either left or right lane, this creates another accident avoidance maneuver from other drivers.
Looks like we mostly have slow pokers from out of state. Are they intimidated ?
How about this theory:
You have someone who is 3000 miles away from home, in their car, and they NEED to be able to make it back home in one piece, and they don't want to have an accident while they are on a cross country trip.
Seriously, do you not even think of this as a possibility?
The safest driving technique is go with the flow (and stay on right lane). When you are 15-20 MPH slower than traffic(cars on left and right passing you at more than 15 MPH) you are in danger of having a traffic accident any second.