Originally Posted by
tjspiel
It all depends on how hard you work. If the road bike encourages you to work harder, then you'll be better off.
This is very true. On days I commute on my fast road bike, I always go like a bat out of hell compared to the days commuting on the fendered hybrid commuter with heavy puncture resistant tires. I attribute that increased effort (aka power output) to trying to beat my Personal Record on Strava segments, which I could never do on the heavy hybrid, since my best times were set using my fastest bike.