Unless the traffic is really slow I will take the lane so I have more operating room. I once descended Monarch Pass behind a cattle truck while touring in CO. The driver actually waved me around but I signaled back that I wanted to follow him. The shoulder was a bit banged up so it was nice to be able to taker the entire lane. If you ever do something like that, make sure you keep your distance in case one of the critters decides to take a leak.