Not sure if this is correct or not, but here is my take. I have found that I think climbing on a SS is easier than a geared bike too. First off, don't think that for one minute that climbing on a SS is not hard. What I am trying to say is, I feel like climbing on the SS is the same action over and over with no increase in difficulty, just me getting more tired. On a geared bike when you are sitting and spinning, it seems to get harder and harder to spin the farther you get up the hill. So, I figure if I get in good enough climbing shape, I will be able to out climb the geared bike with out a problem.
Also, you say you are a bigger guy. Standing uses that weight to your advantage and helps push the pedals down, where sitting down just adds weight to what you are dragging up the hill. :thumbsup: .