Originally Posted by
baobao
redlude97, i'm sorry you took offense in my questions, and mistook them to be cynical;nevertheless, my questions are not answered.
Protracted 16-18% grade, and more-so if it is on loose gravel (try standing up on such a hill), loaded touring bike, orthopedic injuries and limitations, etc. Basically it is an alternate to a triple.
In the case of a 46/30T, you only lose one gear at the top vs. a 50/34T. (50/12 = 46/11 ± 0.01).
cf:
http://www.bikeforums.net/fifty-plus...road-bike.html