Coming home from a tractor show (legit here, right?} Travelling north on I380 north of Cedar Rapids, Iowa, both lanes full at evening rush. Riding in outside lane with comfortable spacing, a guy in a big 'ol gramma cruiser travelling along at same speed wouldn't get over when a semi came up behind him. Semi honked, dropped back and came up fast, he wouldn't get over even though there would have been room if he tried. Went on for several miles, with semi damn near 2 feet behind him. Finally as the suburban exits bled off some traffic, cruiser eased off just in time for his exit. Semi shot into right lane then smoked the tires stopping on the shoulder under a viaduct, two guys jumped out with tools in hand and really trying hard to scramble up the bank to meet the guy at the stop sign. I moved with traffic so didn't see if they adjusted his driving skills. Leo