I find that doing the speed limit eliminates the need to pull over to let folks pass. If I read the law correctly, you only need to pull over if you aren't going the speed limit. That begs the question, why aren't you going the speed limit in the first place?
Where we live, the only roads with paved shoulders are interstates. None of the 2 lane roads have paved shoulders. If for whatever reason I wasn't doing the speed limit, I wouldn't pull over onto a soft grass/dirt shoulder to let people pass.
-Michael