It's not ludicrous, a few hardy souls run it in the winter every year. It's (usually) not terribly cold compared to what you would find on more inland rivers. Once the Bear Camp shuttle route closes, the shuttle gets much longer and more expensive, something around $350-400. The guidebook, The Rogue River - A Comprehensive Guide from Prospect to Gold Beach has a lot of good info about how rapids run at a wide range of levels. Even in the midst of our current run of storms, its only running around 4K.