Can any of us count the number of times some slow poke has gotten in from of you in the passing lane and then seemingly slowed down.

I rode with a guy like this once. He was driving my car at the time and refused to get into the travel lane despite my insistence that  A: he shouldn't travel in the passing lane and B: people won't pass him on the right in Maine because it is against the law. He kept saying he was doing the speed limit and they should too, completely missing the point. So when I saw this sigh the DOT wished they could put up I immediately though of that bonehead. So don't be a bonehead. Leave the passing lane open, travel in the travel lane and for Pete sake drive your own car.

In case you doubt them or me highway pal is here to back us up.

Maine – Keep Right Except to Pass

From: Maine Revised Statutes 29A-2052(6) – “An operator driving on a limited-access way with a speed limit of 65 or more miles per hour is restricted in ordinary operation to the right-hand lane and may use adjacent lanes for overtaking and passing another vehicle, but must return to the right-hand lane at the earliest opportunity. This requirement does not apply to an authorized emergency vehicle, or to a vehicle otherwise directed by posted signs, a law enforcement officer or a highway maintenance crew.”