As others have pointed out, you should be in the drops and weight well back for safety. Personally, I can't just let-r-rip even on familiar descents. I've seen too many deer, dogs, cats, turkeys, chickens and squirrels turn suicidal to trust that one won't pop out of the roadside. I actually know folks who have been wrecked by all of above with the exception of turkeys. In truth, I'm probably no more likely to be able to avoid such at 35mph than I am at 50mph. I guess it's a mental failing but I can't see trying to overcome it at this point.