Originally Posted by
shouldberiding
There's a guy 'round here who I saw with aero bars on his mountain bike. Has knobbies and a suspension fork but he was riding on pavement. I was flabbergasted at the sight of it. Fred factor aside...why?
Another hand/back position is nice. I'd want them even more if I had a flat bar bike. In my case, I have drop bars, so I can already move around pretty well ... but my upper traps tend to get sore after a few hours in the saddle, and a way to force more of my weight onto the lower traps is great. On weekends I like to do long rides on the road bike, but also wind up running errands on the commuter bike, so it's nice to ride around without that soreness clock ticking.
That may or may not be similar to the MTBer's reasoning.