I've driven roads that I would never even in my wildest dreams consider taking a trailer down, places like Shaeffer Trail in Canyonlands, the Flint Trail into the Maze (Canyonlands), Black Bear Pass (Colorado's San Juans). etc. etc.
I've run into Aussies who think nothing of hauling trailers any place their rig will go. A Trillium would, like Robert said, disintegrate, as would most trailers. A few steep narrow rocky roads in the PNW (or Colorado, for that matter) don't even begin to match what these crazies will do. Picture something more along the lines of trying to drive out to Whidbey Island pulling your rig (maybe a bit of an exaggeration, but not much). Don't ever get in a p**ing match with an Aussie. My cousin Mike was an ice roads trucker in Alaska and agrees with me.
And I might add, NEVER buy a used rig from an Aussie. LOL