I'm going to throw my two cents in here....I ride a Big Dummy mostly loaded and a Surly Pugsley with 29+ Krampus wheels (for the summer) in and around the Denver area.....I have yet to use the "Big" ring on either. I have also toyed with the idea of dropping both triples down to 42x32x22. Not sure it'll help much. I may just treat the "Big" ring as a ugly chain guard!
Later