FUCKING. A.
This causes accidents, people stay in the fast lane going under the limit, forcing others to pass on the right = accidents.
In Germany you'll get pulled over with a quickness for not staying in the right lane when not passing, even if you're doing 150+ on the derestricted parts.
99% of the time the people in the fast lane going too slow are on a cell phone.
I don't hesitate to flash my brights, I rarely pass on the right. Tailgating isn't necessary, staying a couple car lengths back with your brights on will give almost anyone the hint.
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