I eyeballed it without looking at the guide -- i.e. without knowing the rating -- and laced up my shoes. My wife looked at the guide and in so many words said, "You're probably not going to be able to do this onsite. Do you want to know the rating?" I said 'no', and that I felt pretty confident from how it looked. I was right. It was challenging, but not desperate. I therefore believe it to be more like 10+, not 11b. Especially with the no-hands rests, as others have mentioned.