We past along that stretch of 70 recently too. Lots of drivers in a big hurry. Lots in a hurry & also on the phone. Try to stay around 1800RPM/67MPH myself. Not too slow & collecting a line behind us but not passing many either. Don't know where all the slow RV drivers are. Sure do have many more blow past us than we go by. Many have way too much tail for the dog wagging away as they race to who knows where.