Several other commuters on my route to work ride road bikes, ranging from low-end to old school to top-shelf race bikes. There is even a guy who commutes on a Transition Pro and blows past me like I am standing still. I still wouldn't have a clue what the guy was riding if I didn't catch up to him at a red light one day. I used to commute on a aggressive geometry road bike as well and it was a lot of fun. I am getting older and finding that relaxing the geometry and slowing down a bit are a good thing. Slowing down to smell the roses and such...

One thing all of those riders have in common is that they really aren't carrying a lot. A couple of them have smallish backpacks but most of them have nothing at all. I assume that they do the drive one day a week and drop clothes off.