Well if you stay in the slow lane with the semi's you won't get run over. It's when you pull out into the fast lane and try and pass a semi that's only going 57-60mph while you're only going 62mph or so that's when you'll get run over. I'm from Oregon and the semis run 55-59 mph here also. But even though the trailer speed limit is supposedly 55 mph lots of towers run 60-70mph. So pulling out to pass a semi we run into the same thing as far as getting run over since non towers are running 70+mph most of the time. You just need to time it out right so you're not being a slow poke in front of a line of faster drivers.
IMO just run 60 mph and when you need to overtake a semi pull out and speed up to get by so you don't slow down the faster drivers.